The Factory Floor

I'm a little tired here, which is to be expected, considering it's after midnight, so I'm going to have a shower, then head to bed for some sleep... However, hopefully I'll be going skating again on Saturday :D

SCPilot

That's good.

12:28 AM

The plan is to go skating in November more times than the rest of my life put together (this is sadly easy to do). I'm at 2 so far

SCPilot

12:54 AM

Cool.

I'm working on some more stuff for the pre-WWIII story for my setting.

Q: What happens if a poster's unwarranted assumptions invalidate their answer when clarifications are made later

8:04 AM

hello

Worldbuilding Meta

9:22 AM

0

I am aware of On editing questions and invalidating answers but this is different. In my thread Would low-grade levitation be of any use? I gave basic rules. As time went by I received a flood of questions requesting further details of the physics. I answered these but in doing so I may have in...

discussion

1:51 PM

@dot_Sp0T hi!

@Green my love!

@Green how are you, do you have time?

@HDE226868 hello oh star of mine

Damn I missed you

(i mean regarding the time)

(..that we were apart(?))

Q: How to steal money if you have a quantum computer?

2:47 PM

@dot_Sp0T Morning!

@Mithrandir24601 This one might be right up your alley:

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I'm writing about whistle blower who discovers that his employer, huge profitable corporation is just a front operation. All their diverse products and services are a sham, and the company is actually making their money from development of a quantum computer. They keep the machine secret and use...

reality-check economy quantum finances

@HDE226868 Are you one of the physics authorities?

@AndyD273 Not on this one.

hmm, k. Just had a random physics question, and it's hard to remember who does what sometimes

@AndyD273 Oh, I thought you were referring to the quantum computing question above. ^^ I can maybe answer a general physics question.

Ok, so double checking my logic; C (the speed of light in a vacume) is a constant no matter what reference frame you happen to be in, and the Planck length is a constant in every reference frame?

2:53 PM

Correct.

So give those two variables being constants everywhere, can 1 tick in Planck time be considered a constant in every reference frame?

@AndyD273 I want to say no insofar as an observer measuring a clock ticking at that rate in one frame may observe a different rate than an observer measuring the same clock in a different frame.

But I'm not 100% sure.

3:09 PM

To my thinking (and if it's wrong I hope someone can explain how), since planck time is a measure of distance as much as it is a measure of time: light in a vacuum travels at a set speed no matter what reference frame the observer is in. The Planck length is set, so light traveling that distance will take the same amount of time no matter what reference frame the observer is in. The observer might see it taking longer or shorter based on their reference frame, but the observer isn't important.

> All their diverse products and services are a sham

You don't need to steal money if you have that many products and services.

And the banking system would catch money theft fast enough and just shut everything down until they figured out what was going on.

Like say Observer A on Earth measures 1 tick of planck time as 1.2 picoseconds*, and Observer B on JeeJorp in Andromeda measures 1 tick as 1.7 picoseconds*, the actual length of 1 tick is the same in both places. (* Not based on real data, just pulling time sounding words out of my butt)

Or another example; I measure a quarter, and you measure a quarter. I say "this quarter is 1 unit wide." You say "this quarter is 2.5 units wide." Even though our rulers (reference frames) are different, the width of a quarter is a constant in both.

So my hypothesis is that if we could build a clock based on ticks in planck time, it could be a universal clock, even if it appears to run faster or slower depending on how much relativity you are dealing with on a local level, and it could be a way to measure local relativity levels, which could be interesting.

I'd love it if someone could help me see any flaws that I'm missing that would be great

3:28 PM

Mornin all.

@HDE226868 oooh, nice! Thanks!

@James Morning

@AndyD273 yes, it's a fundamental constant

@Mithrandir24601 So does that mean the rest of my logic holds up?

Or rather, a constant made of fundamental constants

@AndyD273 yes, what's happening is that your values of a second are different. I should caveat this with 'we don't know what happens at extremely high energies' though

@James rytsas!

3:42 PM

@Mithrandir24601 Cool

@AndyD273 If I'm following, I think we have a similar effect going on with the SI definitions for distance and time. As best as I can tell, they would behave precicely the same.

(Also, it's of order 10^-44 s, which is way smaller than our picosecond on Earth :P )

@Mithrandir24601 what kinds of high energies? The light probably won't go faster than light, no matter how much you juice it up...

@Mithrandir24601 Yes, that's why I put the disclaimer on the end.

The difference would be that the current system of time, seconds, is tied to a physical property of matter, while your system could be tied to a constant of spacetime itself

Does that unit of time have a name yet?

3:46 PM

Around 10^19 GeV of energy, we start hitting Plank Energy. It's not known whether the nice simple model breaks down at that point or not.

@AndyD273 The 'orders of magnitude more than what we've managed to measure so far' kind

Planck really got around... Time, distance, energy... Almost a bad as Stephen Hawking....

Issues would arise when looking at quantum theories of gravity

If it doesn't have a name, would it be inappropriate to call it a universal tick? AKA, the amount of time the fastest thing in the universe can travel the shortest possible distance. or something like that...

Yeah. We have cleared 1800 GeV at the LHC. Far cry from 10000000000000000000 GeV of Plank Energy. Its the same scale as trying to comprehend the fury of the Tsar Bomba, the largest thermonuclear weapon ever tested, by observing the energy released by an apple falling a meter.

3:53 PM

@CortAmmon Poor Isaac Newton...

You just made me not want to be hit on the head by an apple...

@AndyD273 Personally, I would call it "the breakdown point." I have a friend who is now a physics PhD. When he was getting into college, he recounted to the recruiter an attempt by us in the wee hours of the night to define "The Matrix" by discretizing the universe on the scale of plank time and plank length. The recruiter knew enough physics to be able to explain to him that it's not that that is known to be the smallest length and time.

It's the smallest resolvable length and time that our current models predict we will be able to resolve.

We simply don't know what would happen as we turned up the heat.

@Hosch250 It's ever so much fun, and all the cool kids are doing it.

@CortAmmon But are we likely to ever see that kind of heat, outside of a big bang level event?

@CortAmmon Look. When you figure out how to break that, I want to be in the next universe over, OK?

@AndyD273 Never tell me the odds!

You guys are terrifying sometimes.

3:58 PM

@CortAmmon Maybe it doesn't have to be the smallest, so long as it is fixed...

So we could accelerate a wee electron up to those speeds, and its energy would be on the order of 10^9J. I'm in love with Wikipedia's "Orders of Magnitude (energy)" page. There's so many choices to make. That's on the order of the energy of a lightning bolt.... or the kinetic energy of a Boeing 767 in flight.

@AndyD273 It would be interesting if there was something like a harmonic relationship there, a fixed point where the laws of physics are symmetric around.

That electron's energy could also be that of a feather screaming towards you at 5% the speed of light (what-if.xkcd.com/73)

I guess the big question is, if I were to write a story with a "universal clock" which is accurate across all reference frames, and can be used to measure levels of local relativity based on comparing it to an accurate, non-constant like an atomic clock, would I get a lot of physics majors writing me screaming "That's not how that works!!"

Myself, I lost my imaginative spark about these things a while ago. It's terribly hard for me to think of it as anything more than "the limits of my modeling assumptions." I miss being able to take these things further.

What do you mean by "accurate across all reference frames?" That phrasing is tricky

Maybe the better phrasing is "Constant across all reference frames"

irrespective of the observer

Hmm... I do believe you would have to refute relativity entierly to do that.... let me ponder.

Okay, let me try something

4:07 PM

Universal time hypothesis

1 hour ago, 32 minutes total – 11 messages, 3 users, 0 stars

Bookmarked 39 secs ago by AndyD273

We have this concept of TCB. This is a time scale which measures time in the reference frame of the barycenter of our solar system, but as if gravitational effects did not exist. We do calculations to cancel out the effects of gravity distorting time and space.

@AndyD273 a 'Planck time' would work

But it is still dependent on the frame of reference of our solar system.

@CortAmmon I get that. That's not what I'm talking about

You are talking about something which all observes in all reference frames observe as telling the same time?

Hmm... all observers at all velocities at the location of the clock.... it would need to be phrased with respect to the position of the clock, or else we have to deal with the issue that causality is relative.

4:14 PM

@AndyD273 there is a thing in GR that's vaguely similar, where each (I've forgotten the exact words) temporal 'plane', defined as the hyperplanes of space which have experienced the same amount of time since the big bang, get 'threaded' together to define a sort of universal time

This is the sense in which it's correct to say that light from [thing] left [time] ago

That would make sense. Basically defining "epoch" as the big bang, and comparing proper time?

I wonder if I can put it in math terms... C is a constant everywhere in the universe across all reference frames. ℓP is a constant everywhere in the universe. Plank Time = ℓP/C, and should be constant everywhere in the universe across all reference frames.

@AndyD273 this is exactly the definition

@CortAmmon sounds about right

An observer might see it being a different length of time depending on relativity, but it is still constant, and so a clock based on that would be true time no matter what reference frame the observer is in.

@Mithrandir24601 Right. Just making sure I got all the details right. :)

@Mithrandir24601 Though it appears that the formula for Planck Time is different technically

And has a different purpose

I hate words some days

@AndyD273 nope - multiply by c and you've got Planck length by definition

4:32 PM

So this is definitely getting into the wiggly bits of relativity, but what I think we can say is that plank length and plank time are constant at all points and times in the universe, but they are not constant with respect to velocity. Two observes at the same place but at different velocities will measure length differently.

What I think you're trying to do is define one "true" time system for all observers, and the whole point of relativity is that such one such "true" time system does not exist. It's all relative

If you did think you defined such a system, I expect you would see causality violations. Event A causes event B, but for some reason Event A's "time" is 50 units after epoch and Event B's "time" is 30 units after epoch, because it took an accelerating path that resulted in time distortions

Alternatively, you could go back to the aether

Pretend Michaelson Moorley got different results, and identified the aether

@AndyD273 That would define a "privileged" frame. In particular it would be the frame where Maxwell's equations properly describe electromagnetism without requring corrective factors like the Lorentz boost.

Btw, Minute Physics has an amazing series on this: youtube.com/watch?v=1rLWVZVWfdY

The third one (youtube.com/watch?v=Rh0pYtQG5wI) shows the construction of a physical box which can be used to duplicate the exact results the equations of relativity predict.

I'll have to check that out. What is "distance changing at relativistic speeds" called so I can read up on it?

length contraction is the typical term.

That 3rd video is actually really good for explaining that

Quick check: are you familiar with aether theory and Michaelson-Moorley?

@CortAmmon also, getting into the messy definitions of units and what words mean :/

Not really. Isn't aether what they thought space was way back when?

Yes. And then scientists stole the terms.

So the short version:

Over many years, we developed Maxwell's Equations. These are 4 differential equations which capture the behavior of light and other electromagnetic phenomena.

They are simple. Simple to the point of being goregous.

However, there's a funny issue. They don't define any specific frame in which they work.

But they do specify that the speed of light is a constant.

The speed of light just falls out of the equations naturally.

So this lead to the question, which frame do these equations work in?

One popular theory was aether theory. This theorized that light travels through some medium, called the aether, just like a baseball travels through the air or a fish travels through water.

If this was true, then the frame where the aether stood still would be a very natural reference frame for Maxwell's equations.

4:43 PM

N Planck times is a number that depends on units. These units then depend on velocity and observers, is one way of thinking about it - it's not that a Planck time is relative, it's that the metre stick used to measure it is relative

Just like if you and I were talking on a train, the natural reference frame for describing the propagation of sound through the air between us is the one where the train (and thus the air) is still

So thus, scientists went out to go try to measure the speed of light in different frames to watch its velocity appear to change (just as the velocity of a ball thrown on a train appears to be much higher to a person standing on the ground than it does for a person standing on the train)

They did many experiments, but the most definitive was the Michaelson-Moorley experiments

They looked at starlight at different times of year, when the rotation of the Earth around the sun imparted a rather large velocity to our measurement apparatus.

@CortAmmon To be fair, the air inside a sealed cabin would be still, even if the train wasn't... :)

@AndyD273 so a better answer to this is: it depends on what exactly you mean

They expected to find the aether. What they actually found was curious: the speed of light was the same, no matter what velocity or orientation one was traveling in!

@CortAmmon I know that one

4:45 PM

It'd be like the guy on the train and the guy on the ground both agreeing that the ball is traveling at 20m/s from their perspective. It simply doesn't happen.

Even at .9C the speed of light would be a constant

So that buggered lots of scientists

Yes, we now know that at .9C, the speed of light woudl be constant in all directions, but that wasn't immediately obvious to the scientists back then. They hadn't had that concept drilled into them in highschool physics =)

So they had to sit down and say "okay, how can we make these equations work. They are doing stupid things that don't make sense."

And what they came up with was called the Lorentz boost.

If you took the velocity of the observer, you could apply a corrective factor to the time and positions in Maxwell's Equations. This gave you a consistent result no matter what frame you were in.

So this made people happy because it meant there was still some magical reference frame where light traveled according to Maxwell's original equations, but still worked in all reference frames.

But it made people sad because, frankly, the modified equations are ugly.

Maxwell's equations are pure to the point of brilliance. With the Lorenz boost applied, they're just this murky ugly beast to make undergrad student slog through on exams.

This was the environment Einstein came into.

Einstein had a brutally brilliant assumption: The laws of physics were the same for all non-accelerating reference frames. There should not be a Lorentz boost that was frame-dependent.

And so he made the crazy declaration: time and space itself is relative to the observer.

He packed the Lorentz boost into time and space itself.

This ends up describing everything exactly the same as before, except now we pay some funny prices. If two observers are in different reference frames, they simply do not agree on how time and space are stretched.

He argued there is no universal causality. Two observers can argue that two events happend in different orders, because their mapping of space and time is different.

While Maxwell's equations with a lorentz boost argues that light travels through time differently, Einstein argued that everything traveled through time differently.

That a clock, flown around the planet a few dozen times, will have ticked slower.

And, when the experiments were finally done, it turned out he was right.

Right, I know all that (just not the names)

The time constants of things like springs or biological apparatii or electron band-gaps all distorted in the same way the time constants for light were distorted to keep t he speed of light constant.

I had forgotten about distance contraction though

4:54 PM

In other words, it's like the center-of-the-universe thing.

Either you can make weird equations and make earth the center of the universe, and things still work.

So fundamentally, if you want some "proper" time, you have to challenge relativity. Start by undoing Einstein's fundamental assumption that all intertial frames are proper.

Or you can have nice ones and model the sun as the center.

s/universe/solar system

You'll need to come up with some reason why one single inertial frame is "proper," and all others are "improper."

The usual way we do that is to define it. "Hey, the frame at the barycenter of the solar system is proper. All others aren't." But if you want to tie it into physical constants, the physics of the universe will need to define it

Which, with a little literary license, could be thought of as the throne of God.

@dot_Sp0T I do now. What's up?

That's why I tried to define the terms early on (even if I fat fingered vacuum)...

4:59 PM

If you don't unseat Einstein, however, you'll end up chasing you tail, like trying to find the smallest uninteresting number en.wikipedia.org/wiki/Interesting_number_paradox

I do wonder if there is some way to find something that doesn't get contracted at speed, like the orbit of an electron or the width of a lepton or something...

If it did, then it would be a discovery, similar in magnitude to discovering the aether

Looking back at your definitions, to be very precise, plank length and plank time are constants in every reference frame, but observers in different reference frames will disagree about their values.

You could certainly use such a discovery to anchor your universal clock.

I think that we also disagree on the definition of "contants" :)

Maybe its something that occurs in the mismash of gravity.

@Green I felt like I did a bad job at explaining the issue I saw with an answer and wanted to ask you if you saw where I could've done a better job.. worldbuilding.stackexchange.com/a/130439/2746

5:03 PM

@dot_Sp0T I'll have a look.

Also I wanted to ask if we were still on track with the choco-exchange and if there was anyone else wishing to join?

Well, for Einstein's formulation, he started with the concept of a rod and a clock. A rod is a perfect measure of distance, and a clock is a perfect measure of time, both within the reference frame.

You've simply assigned values to those distances as times, from Plank

@CortAmmon Or string theory... (assuming it's separate from gravity.)

True. One other place where some universal time could crop up is in the resolution of quantum gravity.

The distorted space-times of GR give QM fits

its not yet known whether GR will cave in, QM will cave in, or if they'll both have to bend and adapt to work together.

(most likely the latter)

@dot_Sp0T Yep! I'm still up for a chocolate exchange.

5:06 PM

@Green it's not gonna be a big parcel this year bc I have to watch expenses, I'll see if I find some fancy chocolate bars to put in a padded envelope tho :)

@CortAmmon I guess by Constants I mean like C is. Doesn't matter your reference frame, your acceleration, anything. It's always the same for everyone everywhere.

Ahh

@dot_Sp0T That's perfect. I'll find a good American chocolate.

Have you ever heard of Tcho chocolate? They're based out of San Francisco.

*Chuckles* Just look at how much {bleeping} trouble making C be constant is. It shredded the desire for a constant of time! How many more constants do we want??!

All of them

If there is one, it's not impossible that others exist

5:10 PM

Newton's era was a good era =)

It's the only one I know of, so if a story needs another constant like that, then the first step would be to write a new one that isn't part of mainstream physics.

@Green i never had any america-produced chocolate before the one you sent me I think

maybe some M&Ms

@dot_Sp0T The responder's answer feels like a valid one. I'm not sure why he invoked 'magic smoke' or magic anything because conventional chemistry can get you smokes with different colors.

well, the only one which involves motion. There's ones that lead up to the speed of light, like the permitivity of space.

@dot_Sp0T M&Ms are garbage chocolate. There's way better stuff available.

@Green the magic stuff is all I am complaining, and what I am basing my downvote on.

Skittles are the best chocolate there is

5:13 PM

@dot_Sp0T Really?!

The real trick with constants is that they can become incompatable.

@dot_Sp0T I'm not sure why he included magic smoke that doesn't pay attention to air movement. A science-based tag on your question would have helped cut down on that.

If you have one group of invariant constants (like C, permitivity of free space, etc.), and then you define another group, they can start conflicting over how to work with things like space and time.

The first part is a good answer but the magic smoke that doesn't move is unnecessary.

I think your language is a tad inflammatory but not anything too bad.

Eh, the more I read it the more it feels like the guy was defending his answer and you were pointing out why it wouldn't work for you. No harm, no foul. I wouldn't worry about it.

5:30 PM

@CortAmmon yeah, this

@dot_Sp0T wait, choco-exchange?

@Green I don't feel that we should need to include science-based to tell people to not base their answers on introducing magic to the world of the question. That should be inherently clear, not?

@Mithrandir24601 yes

@Green any specific words? I can work with that :)

@Green thanks for taking the time to help me out!

@Hosch250 naturally

@dot_Sp0T as much as I'm interested, I do have dietary problems that would probably make it too complicated

Hmm... curious... does the doppler effect break the idea of using the wavelength of light as a way to measure it? Say you have a wavelength of light at a certain energy level, like x-ray, and then you accelerate uptoward relativistic speed, the doppler effect will appear to change the wavelength; shorter ahead, longer behind, as you accelerate toward the light source... But the wavelength isn't actually changing, you're just running into each wave crest faster than you would if you were at rest

@dot_Sp0T An explicit call out to say "I want normal physics for all other things except these airships fly. Don't handwave anything else." I didn't notice you said that but it would be my assumption when answering your question.

@dot_Sp0T No, I don't think so.

@dot_Sp0T I'm happy to help anyone who genuinely wants to understand and get better.

@dot_Sp0T Implicitly, the rest of your question has a good "keep this real science" feel to it which I why I would have assumed a science-based answer to your question.

@Mithrandir24601 tell me of your dietary problems

@Green I will add a notice on top(?)

5:42 PM

@dot_Sp0T I can't have dairy or egg. I'm also in the UK...

That doesn't sound that difficult

@Mithrandir24601 That's OK. We'll send you carrots.

Green is in the US. I'm in Switzerland

@dot_Sp0T You may not need to. If the other answers correctly got the implicit "No magic" vibe the same way I did, then a notice probably isn't needed. It's just that one guy.

Let's just set up a site-wide secret santa.

Anyone can volunteer, and everyone can just do one person then, instead of turning it into an NxN network.

(Or a chat-wide, or something.)

5:46 PM

@Hosch250 I think I trust people in chat with my mailing info way more than some rando Wubber (nothing against rando Wubbers, I just don't know them).

@dot_Sp0T ahh, Ok, this sounds possible - what are the details?

(As in, how does this work?)

@Green Reasonable.

@Hosch250 I'm only interested in chocolate though :P

:)

@Mithrandir24601 we find a way to exchange addresses (e.g. me an Green did it through Steam - which means our Steam tags are in this chat, but not the addresses as they were on a different - non-logged chat) - then we send chocolate to each other

5:48 PM

IRC FTW there.

@dot_Sp0T I like this idea... Is there a recommended spending amount?

@Green I find that if I can clear it up for one person, I made the question better

@Mithrandir24601 whatever you are comfortable with. I went a tad overboard last year with what I sent Green tbh...

@Mithrandir24601 As much as you want to send to someone you've never met in person? I didn't go above $20US.

@dot_Sp0T Do your pleasure then :)

@Hosch250 I didn't say this cough but, I can create private rooms, for moderation purposes only, of course

LOL.

5:49 PM

Also, as I study German, I'm becoming far more aware of the structure of clauses in a sentence.

@Green Does it apply to santa clauses, or just word clauses?

@Hosch250 Both!

@Green this seems very reasonable and tasty...

@Green I did

@Mithrandir24601 they are still logged though

@dot_Sp0T I shared my email address with James at a time I knew we were both on; he acknowledged that he got it then I deleted the message. Probably won't stop a mod from getting it back but I'm not worried about the mods.

5:58 PM

@dot_Sp0T Probably? Anyway, exchanging personal information is easy

A: Sandbox for Proposed Questions

We'll find a way somewhen over the weekend surely

Feeds 4026

7:36 PM

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how can a supercontinent lead to sex/gender equality in the middle ages I was told that this question was too broad and want opinions on how to make this acceptable. Our planet's continents (Africa, Asia, etc) remained connected without breaking up into different landmasses. Because of this, mos...

7:56 PM

Whats shakin all

you are

when I am done with you

Recent Questions - Worldbuilding Meta Stack Exc…: What motivates the dead?

8:08 PM

that came out wrong

Worldbuilding Meta

8:20 PM

posted on November 16, 2018 by Quinnland23

No brain eating zombies. I'm talking about sometime more akin to the afterlife. In the world of the dead, what would my motivations be? Assume a spiritual world where regular food is not required, and "material" possessions have little significance. I don't need to earn a paycheck to keep a roof over my head and if I'm not chasing a career, I don't need to climb a…