"If we do not have causality, we are buggered"...

[eFestivals]

This paper talks about time stamping in neutrino experiments back in 1999. Done with GPS, but only with a 100ns accuracy. I'd be suprised if that was good enough for a speed experiment.

that's exactly what I'd thought, and how we got to discussing the ability to have a fixed reference point to measure from.

If you know the variance of the timing method and you run the experiment enough times (I'm guessing they've got loads of times), then you can average out the error in timing and incorporate it into the statistics

the reports say they did the experiment 15,000 times - which is certainly a big chunk of data to work with.

But to me it still seems an untrustworthy conclusion when the variance is greater than the resulting average they've used for that conclusion.

[eFestivals]

ahhhh .... just spotted that they claim a margin of error of 10ns - so presumably that comes from the timing reference point.

And with with result being 60ns faster than the speed of light, that defo makes more sense, and probably gives it the statistical relevance that they claim.

So I'll shut up now.

[Ed209]

15000 is a hell of a lot of data. When averaging something with a known variance, then the variance of the average is effectively that variance divided by the number of times you've run the experiment. So 15000 times will reduce it down a lot. they'll now know what the variance of the averaged data is so they can construct confidence intervals. With that new reduced variance they can say 'I'm 99.99% sure the speed of a neutrino lies within this interval'. If that interval lies completely above the speed of light then hey presto, your 99.99% sure they are travelling faster than the speed of light

something like that anyway

[eFestivals]

15000 is a hell of a lot of data. When averaging something with a known variance, then the variance of the average is effectively that variance divided by the number of times you've run the experiment. So 15000 times will reduce it down a lot. they'll now know what the variance of the averaged data is so they can construct confidence intervals. With that new reduced variance they can say 'I'm 99.99% sure the speed of a neutrino lies within this interval'. If that interval lies completely above the speed of light then hey presto, your 99.99% sure they are travelling faster than the speed of light

something like that anyway

it's a very long time since I did stats in any depth, and while what you say rings true to me as general idea, I don't think it holds true when the variance is greater than the result you get from using that variance.... which was where I was coming from in talking about this.

But anyway, having re-read the article that Tony started this thread with and noticed what I failed to take in on the first read - that they say there's a margin of error of 10ns - that idea of mine ceases to be relevant.

Or at least it does if the margin of error they're talking about comes from the possible variance of the timings, rather than it being a statistical margin of error. If they're talking about a statistical margin of error then I'm unsure again, and every time I try to think it thru my head spins.

[Istari]

Great Scott!

[fred quimby]

15000 is a hell of a lot of data.

Edited September 23, 2011 by fred quimby

[worm]

Yet as feral said, the method they used isn't called science, it's called make-it-up-as-you-go-along-so-that-psychology-is-always-right.

So yeah, the hypothesise are wrong, the hypothesise of that thing that gets called psychology.

[grumpyhack]

Next they'll be telling us that everything we learnt watching StarTrek is wrong and that the earth isn't flat.

It's all fascinating stuff but I don't quite see how it solves the world's problems of flood, plague, pestilance, earthquakes, famine, corruption, politicians etc.

[Ed209]

Next they'll be telling us that everything we learnt watching StarTrek is wrong and that the earth isn't flat.

It's all fascinating stuff but I don't quite see how it solves the world's problems of flood, plague, pestilance, earthquakes, famine, corruption, politicians etc.

[feral chile]

Who knows, it might lead to time travel, at which point someone can go back into, wipe out the human race before it ever got started and solve all those problems in one go, apart from earthquakes of course, but there's not a lot we can do about them

[feral chile]

Paradox.

Time travel has existed since the universe began. You're traveling through time right now at 1 second per second.

[Ed209]

I don't think time travel's possible, else there'd have been reports of people from the future visiting past events. I can't believe humans would be careful enough to leave no trace.

Unless that's where all the God myths come from, of course - maybe they only travel back to eras where people wouldn't guess where (when) they were from.

[Ed209]

Paradox.

Time travel has existed since the universe began. You're traveling through time right now at 1 second per second.

[feral chile]

I wasn't really being serious. Causality issues would make backwards time travel a very dangerous thing and really doesn't make any sense. Although there's no way we could ever tell that travelling forward in time is possible. They'd obviously get stuck there though.

[Ed209]

I don't know why, but I expect these findings to have an explanation that doesn't desecrate what is known as 'c' and its meaning and relevance in science.

They probably need to send their kit off for cal or summat ...

[Ed209]

yeah I wasn't being serious either. It fascinates me though - like you say, it screws around with causality, so lends itself to 'what if' scenarios.

Time is one of the things that humans have no control over. So the idea of time travel, of gaining control of time, and of causality, is appealing.

[feral chile]

If it was the case that history and hence the present were not fixed and in a constant state of flux then reality would cease to exist, we couldn't trust anything as being the truth, the world around us would be continuously changing and morphing, sometimes drastically, we would even come in and out of existence in instantaneous moments. It sounds like a nightmare

[Ed209]

How do you know that isn't happening? If reality kept shifting, so would our consciousness of it. And when it changed, we wouldn't be able to remember the difference, because all our causality would have changed with the rest of reality. So we'd only remember the particular reality we're in.

(Isn't that the theory behind parallel universes?)

[eFestivals]

They use the scientific method. If they don't, then it isn't scientific.

a scientific method includes accepting the results of any experiment.

So, from what feral said, it cannot be that scientific methods were used.

Your understanding of science is clearly shit.

says the man who thinks that the results of a scientific experiment can be ignored for 'scientific' convenience.

What Feral was saying has absolutely nothing to do with psychology.

PMSL. 'Psychology' is the idea of those who call themselves psychologists. When psychologists have a laughable scientific method it's everything to do with psychology.

It has everything to do with the scientific exploration into identifiable variables. A task that is harder in the humanities as there are far more of them than in the physical world.

yep, it's certainly much harder when there is only guesswork and unprovable ideas to work from.

And it becomes harder still when they work from those guessed-at indeterminates and say that anything which doesn't fit their guesses is wrong, which is what they do (as proven by feral's statement).

That's what Feral was asked to explore.

except feral wasn't. She was asked to not contradict accepted but unproven psychological dogma.

[eFestivals]

I don't think time travel's possible, else there'd have been reports of people from the future visiting past events. I can't believe humans would be careful enough to leave no trace.

one of the theories around this is that time travel backwards isn't possible, but that forwards time travel is.

[feral chile]

a scientific method includes accepting the results of any experiment.

So, from what feral said, it cannot be that scientific methods were used.

says the man who thinks that the results of a scientific experiment can be ignored for 'scientific' convenience.

PMSL. 'Psychology' is the idea of those who call themselves psychologists. When psychologists have a laughable scientific method it's everything to do with psychology.

yep, it's certainly much harder when there is only guesswork and unprovable ideas to work from.

And it becomes harder still when they work from those guessed-at indeterminates and say that anything which doesn't fit their guesses is wrong, which is what they do (as proven by feral's statement).

except feral wasn't. She was asked to not contradict accepted but unproven psychological dogma.

Edited September 25, 2011 by feral chile

[feral chile]

does 'time' exist? ... the way we conceive it?

Edited September 25, 2011 by feral chile

[rabid]

does 'time' exist? ... the way we conceive it?

[grumpyhack]

Mrs GH is currently on holiday in Australia and we Skyped today. They are 8 hours ahead of us in time so my morning was her evening. I've always liked to fantisise that if you could fly round the world fast enough against the flow of time that you could get home before you'd taken off. (Only a silly idea. No need for explanations as to why it's not possible, unless you want to).

Oh and I reset the clock on my computer so I'm posting this before I've written it.

[feral chile]

Isn't that the only way it can exist?