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The Skeptical Zone
"I beseech you, in the bowels of Christ, think it possible that you may be mistaken."
Here is something that is worth arguing over.
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Along those lines, I have actively tried to find more information about the latest test of relativity on clocks. If you type that into google, the majority of hits you get once again refer you back to Hafele-Keating- which knowing how bad the experiment was, doesn’t generate a lot of confidence in what you find online when they still continue to refer to that experiment everywhere you turn.
The few others you can find are mostly concerning one in 2010 by the National Institute of Standards of technology, which did an experiment on clocks, separating them by as little as half a meter in height and supposedly getting different results in the times registered, due to differences in gravity. This study is talked about in many mainstream science journals, but that’s about all you can find. By now I am well aware of how mainstream science journals treat truth, so I remain dubious about this study. There seems to be very little follow up on the discussion of this study since 2010. That seems rather odd. (There is also one done more recently that apparently hasn’t been peer reviewed yet.)
One has to be very skeptical of how this could effectively be measured. 1/2 meter in height? Where was this done? Would just the different differences in densities of matter at different spots around the globe affect the gravity at any one spot on earth? If I move ten meters to the right or ten meters to the left, and there is a different structure of rock under my feet, isn’t that going to change the gravity? Are there scales that can test gravity to this precision?
Again this seems very dubious, and it is even more suspicious by the fact that there is no discussions about this anywhere.
They also did a test where one clock was moving at 20 miles per hour and one was stationary and the moving clock supposedly went slower. This one also seems problematic but I can’t get more information about it so far. Which clock was moving, was it accelerating? If one is moving at a constant 20 mph compared to the other, then neither can be said to be moving faster than the other….
Hm..
Now does it mean that all of this is wrong, of course not. But what it does mean is that some may have things to say that could rightfully question some of these assumptions.
As far as I know, people do challenge Einstein. The challenges that are said to be crank science are the ones that demonstrate that they don’t know what they are talking about.
I’ve disagreed about the importance of natural selection. I don’t think I have been called a crank. On the other hand, I do not claim to be an authority.
I see the same thing in mathematics. People try to trisect angles or square the circle. And they genuinely are cranks or crackpots. The same with claimed proofs of Fermat’s last theorem. But then Wiles came up with an actual proof of Fermat’s last theorem, and it was recognized and accepted. The branding of people as cranks isn’t as far off as you seem to think it is, though I’ll agree that it can occasionally go wrong.
Mostly in the peer reviewed journals. Probably also in coffee rooms of university science departments.
They are human. Humans like to form groups with others who think alike.
You apparently think anything less than 100% agreement by anyone in the physics community is not a consensus. This is not really correct.
There are always authors who suggest alternative interpretations of phenomena, even though they generally support “the consensus”. This is in the nature of science and part of a longer process of hypothesizing, testing and debating results.
To pick a current example:
In order to explain the structures, the movement, and cohesion of distant galaxies and galaxy clusters, physicists have generally invented this term called “dark matter”, which refers to an unknown source of gravitational attraction that does not interact with electromagnetism and is therefore invisible to light. This extra, but “dark” source of gravity which can’t be directly seen in telescopes, is supposed to explain why galaxy clusters stick together and why galaxies have the structures they do, among other things.
But alternative theories have been suggested even by some “dark matter” proponents. They say something along the lines that while there is good evidence for einstein’s theory of general relativity, it is also possible that general relativity breaks down under large cosmological distances and so is ultimately wrong. That there is no dark matter, and that a different theory of gravity explain the structures of galaxies and galaxy clusters. And they have published their proposals and hypotheses in the physics literature. One doesn’t become a crank simply by proposing alternative hypotheses.
It would seem rather strange to claim that there is some sort of conspiracy against doubting or proposing alternatives to Einstein’s theories of relativity, when you are here linking examples of papers that do that very thing.
But again, just because you can find such examples does not mean there is not a general consensus by a large majority of physicists, that Einstein was probably still correct.
When claims of bias and conspiracy becomes the excuse for why some guy’s New Pet Theory(tm) doesn’t find instant agreement from the broader scientific community, it is then that it moves into crankery territory. Anyone is free to publish their alternative testable interpretations, but it is when they insist they’re out to get them they become cranks.
Right. Thinking alike instead of thinking for yourself-that is the antithesis of being skeptical.
You mean they can’t censor the entire internet??
Wow, what a revelation you have noticed Rummy!
You understand that such proposals are published in mainstream scientific journals, right?
That’s a false dichotomy.
You can think for yourself and agree with someone else who has independently thought the same thing. Being part of a group isn’t in and of itself evidence that you can’t think for yourself. Most people could independently work out that 2+2=4.
The alternative here is that you must think all groups are inherently gullible because their members agree on some range of topics. I think you should go to places like uncommon descent, and Evolution news & Views, and tell them this.
Rumraket,
So there is a scientific consensus or there isn’t?
It’s one you wouldn’t answer, certainly.
Rumraket,
Or TSZ.
Humm, let’s see what we can agree on,
When you asked “Into what shape?”, I replied:
Now, you do realize that if your horizontal-for-Sarah dome is smushed along the direction of its motion relative to the train, like I wrote, then that means that the first edge Adam encounters must be higher than the second edge? This is grade school geometry. I suspect that you made this mistake because you thought that the direction of smush was parallel to the track. It isn’t.
I am a little disappointed that you mis-understood MY two-trains-crashing question. It isn’t another paradox, it is High School Physics, done wrong. The question is, is phoodoo smart enough to spot the mistake?
There’ll be a follow-up comment.
Moving on.
As I understand it, Jefimenko isn’t making the argument phoodoo thinks he’s making. AIUI he is arguing that certain experiments/phenomena that are viewed as experimental confirmation of SR are not experimental, as such. I think I see his point re the Stanford Beam, in our frame there is a magnetic field that slows the spreading of the beam. In the particles’ frame, there is no such magnetic field but, thanks to Lorentz, the predicted result is the same. It’s just another way of deriving magnetism as a SR correction to electrostatics, apparently.
Regarding time dilation, his argument strikes me as rather lame: he constructs a harmonic oscillator clock and shows that will run slow at relativistic speeds. Again, he has merely demonstrated that the Laws of Physics still pertain under Lorentz transformation. His argument is that because he can derive a “cause and effect” explanation for why the behavior of a particle beam or a harmonic oscillator can be explained in different frames of reference, the experimental demonstration of any relativistic effect cannot be viewed as experimental support for SR.
Do atomic clocks use harmonic oscillators?
TL,DR version: what Neil said.
But you’re here, aren’t you? You and Mung and Bill Cole and Sal Cordova and Vincent Torley and so on. I was of the impression this website exists because, as opposed to so many other ID-mostly or Skepticism-mostly echo chambers, we are here to argue with each other?
If I only wanted to hear from “my side” of this issue, I wouldn’t come here at all.
Fine, so the first edge Adam encounters, according to Sarah, is much lower than it is for Adam. So according to Sarah he will smash into the first edge, and according to Adam he won’t.
How does that help you?
Oh dear, we have covered this already. Adam and Sarah agree about the height of the edge that Adam hits at the moment of impact. They disagree about the height of the other edge at the moment of impact.
Simultaneity is a function of location.
Figured out the two-trains-crash problem yet?
DNA_Jock,
Why can’t it already be covering part of the opening before he enters, so that for Sarah, there is no room for him to pass by, but for Adam there is?
Either way you tilt it it is high enough from one of their perspectives, and not enough room from the others.
You really need to work on your visualization skills.
Why do I care about the two trains crashing problem, it has something to do with this thought experiment? I don’t think you have shown how it does.
You still don’t think it matters what angle the dome is tilted at impact? You think any tilt results in the same distribution of force?
It’s a thought experiment. Show a little imagination. And don’t be afraid. The average 7th-grader would have no problem answering these 2 questions.
I’ll ask again:
– Will the noise generated by the doors fully closing reach Sarah at the same moment (stationary and equidistant from the doors)?
– Will the noise generated by the doors fully closing reach Adam at the same moment (equidistant from the doors but moving toward one)?
And for the record, sound is not a ‘different medium’. Sounds is not a ‘medium’ at all.
Your grasp of physics appears to be every bit as abysmal as your grasp of theology.
RoyLT,
I find your objections pedantic and trite. Sound waves are a medium. You have not shown how that has any relevance to relativity.
Thus its pointless.
Because at the moment Adam passes underneath/into an edge, Sarah and Adam agree about the height of that edge. They disagree about the height of the other edge. How many times do I have to point this out?
No.
Yes, it does. Once things crash into each other, all sorts of stuff happens. The burden is on you to demonstrate that Adam’s view of the collision is inconsistent with Sarah’s view, because Adam thinks the CoG of the dome is fractionally higher at impact than Sarah does. Which you have not even tried to do – all you have done so far is to assert that they must be inconsistent, based on your wonderfully naive intuitions about rigid bodies.
To be clear, I have not figured out the resolution to the angle-of-tilt paradox — hey, maybe you are onto something here, but you have NOT EVEN POSED IT yet. You need to demonstrate that Adam’s view of the collision is inconsistent with Sarah’s view. I don’t believe you are capable of doing this, and my belief is bolstered by your reluctance to explain, in the two-trains-crashing scenario, how Adam’s view of the collision is NOT inconsistent with Sarah’s view.
I see Joe G has competition.
A wave is not a medium. Waves are perturbations that move through media. Please educate yourself.
My question is specifically tailored to answer this aspect of the thought experiment with more rationally attainable speeds. Its relevance is clear to everyone but you. Or more likely its relevance is obvious to you but you rightly see that answering it will compromise your ridiculous position.
Wait, your argument is now, “Oh, what’s the difference if the impact is slightly different, who is going to even notice, the train is going fast?”
Different is different Jock.
phoodoo,
Yeah, that’s what I thought — you are unable to describe (y’know, with math’n’stuff) precisely HOW Adam and Sarah will disagree about the collision.
It’s okay.
But until you do, you don’t have an argument, just an intuition.
“An impulse through the CoG is distinguishable from an impulse at an angle to the CoG.” Yeah, that’s true for classical mechanics, but the situation is more complicated at relativistic speeds. For one thing, you cannot rely on that idealized “elastic collision”. I genuinely think that it’s an interesting problem, but you have yet to even STATE the problem.
Given your track record, forgive me for not finding your intuitions compelling… M&M’s, anyone?
The math is really hairy.
Did you figure out the apparent two-trains-crashing paradox yet?
Baby steps.
Some speeds are more relativistic than others?
Depends whose asking.
https://physics.stackexchange.com/questions/185116/what-speeds-are-fast-enough-for-one-to-need-the-relativistic-velocity-addition
https://en.wikipedia.org/wiki/Relativistic_speed
What if TIME is an illusion?
I’ve been thinking about phoodoo’s collision.
Let’s assume, for the purposes of phoodoo’s thought experiment, that in addition to Adam and Sarah being immortally indestructible, that the dome and the train are made out of unobtainium*, a metal with very high Young’s modulus and shear modulus, and near infinite heat capacity.
Thanks to changes in gamma due to the acceleration of the part of the dome in contact with the train, and the deceleration of the front of the train, Sarah will see a small contraction of the dome and a larger expansion of the front of the train. Adam OTOH will see a small contraction of the train, and a larger expansion of the dome. At least initially, I reckon that these effects will be small compared with the familiar compression and expansion due to the unobtainium-on-unobtainium impact.
In the first nanosecond following the impact, Sarah will see:
The part of the dome close to the contact point stretch (although not as much as Adam sees)
The front of the train compress (although not as much as Adam sees)
Sarah will see the part of the dome in contact with the train get a bit heavier, and Adam will see it get quite a lot lighter.
Sarah will see the front of the train get quite a lot lighter, Adam will see it get a bit heavier.
And they won’t agree about when that nanosecond starts or ends.
I said the math was hairy. How’s your vector calculus, phoodoo? Is it up to the challenge?
The one thing Adam and Sarah can agree on is that the CoG of the bottom edge of the dome will be below the train well before the deformation of the dome reaches the half-way mark. Unless, hey here’s an idea: what if the dome and the ground are made of ultra-unobtainium, such that, upon contact with the ground, the dome ceases its downward motion instantaneously. That simplifies things a lot.
It also makes phoodoo’s paradox go away. Sarah and Adam will view the collision identically. Oooops.
If you are having trouble seeing why this is the case, we can start with baby steps, phoodoo: have you figured out the High School mistake in the apparent two-trains-colliding paradox yet?
*it’s an aerospace term
DNA_Jock,
Yea, and maybe the sun is in Sarah’s eye, or maybe she blinks, or maybe people can’t watch trains moving near the speed of light, or maybe she is checking her text messages.
You seem to think the thought experiment relies on Sarah actually seeing and analysing what happens. Jesus, if that is what you think no wonder you can’t imagine it.
They are different events. That’s what matters.
And the dome never hits the ground. And the dome never hits Adam, according to Adam, because the front is smushed and not blocking the entrance, but according to Sarah, its not smushed so the front edge hits Adam just as he is entering.
You know in thought experiments, you can see whatever you want, you get that part, right? Maybe the problem is you believe its a math problem. Do you know you also can’t see numbers?
Oh dear, phoodoo,
I took it for granted that you understood that “sees” means what each observer records using their infinite array of synchronized clocks with an infinite array of time-stamped (very) high speed cameras. My apologies, I over-estimated your understanding here.
At any point where Adam is, Adam and Sarah will agree about the vertical position of the part of the dome directly above Adam (give or take a factor of gamma for the vertical motion of the dome, which we can happily stipulate is tiny). We have covered this already. For all other positions they disagree about what time it is, and therefore, pretty much everything else.
That’s a rather entertaining way of phrasing it. Better to say “You can record, for later analysis at your leisure, exactly how things appear from your frame of reference. ”
It’s truly impressive, phoodoo, that you have overturned a famous relativity paradox, without using any math at all, just your intuition.
Either a generation of physicists are wrong, or your intuition is. That’s a puzzler.
Care to try again, this time with math?
As a warm up, have you figured out the mistake in the apparent two-trains-crashing paradox?
ETA if Adam hits the dome before entering the tunnel, there’s no paradox.
They didn’t cover this in the science fiction novels I’ve read.
They didn’t cover it in any of phoodoo’s physics classes either.
Did they in yours?
DNA_Jock,
I am not sure what you are now trying to claim here. Either Sarah and Adam agree on the parallel edge of the dome, or one thinks one edge is higher than another. In either case you have two different results, in which case why couldn’t a high speed camera capture the difference? A collision with an angled dome is certainly going to be different than a level one. Or no collision at all is certainly going to be different than a collision.
I can know that with virtually no math at all, you know why? Because math is supposed to be a representation of some reality.
We’ve covered this multiple times. They disagree about the angle of the dome, but not about its height where Adam is.
“certainly” Really? You need to demonstrate this. And you cannot. FFS, phoodoo, Adam thinks that the dome is HEAVIER than Sarah does. But they will still see any collison as being consistent with the laws of physics, for their frame of reference.
This is the only correct thing that you have written
Yeah, just like you knew that a single M&M would get eliminated every time. There are aspects of reality that are counter-intuitive. It really doesn’t matter what you assert without support.
Have you figured out the two-trains-crashing mistake yet?
Would you like it explained to you, or is wallowing in ignorance more comforting to you?
DNA_Jock,
You are still claiming victory about M&M’s even though you need to have about 100,000 generations for them to fix, and you need one individual to have a births in 10 different generations? Wow, that’s pretty pathetic Jock.
And it still doesn’t mean that colluding with a dome that is level with the ground and one that is tilted in relation to the ground is the same event-those are different events. Even without math you can know that. No sports huh? Maybe it would give you some common sense.
You have also yet to explain why I should care about your trains colliding. Do you think it doesn’t matter what angle they collide at too?
Victory, schmictory. Your rather esoteric definition of ‘generation’ is neither here nor there, I was merely pointing out that your intuition, e.g.
is not a good guide to reality.
Yeah,it doesn’t mean that it’s the same, but it doesn’t mean that it’s different, either. You need to demonstrate that it’s different (and in what way), rather than merely assert. Your intuitions about rigid bodies are leading you astray.
It’s a useful way of introducing you to the idea that observers in different frames can see the same event rather differently, but still consistent with the unitary laws of physics.
Let’s see.
If the two trains collide at an angle that differs from ‘head-on’ by Θ, then Sarah will see 900 MJ x (cos(Θ/2))^2 energy dissipated, whereas Adam will see 1800 MJ x (cos(Θ/2))^2 energy dissipated. Still off by a factor of 2. If they both measure the temperature increase in the wreckage, then they will disagree about the laws of physics. Thus, there’s a mistake in their calculations.
(See what I did there? With the math’n’stuff?)
Although, if you think about where the (sin(Θ/2))^2 energy went, you might spot the mistake.
ETfixlink
DNA_Jock,
Maybe you better go back and think about the M&M’s first before you start worrying about trains colliding. With a population of only 99, it still took 1000 runs, going nearly 10,000 generations for it to fix, AND that is with absurd notions of a generation. If you upped the number to 1000 individuals, I think it needed like 1 million tries. One time it needed five million generations.
Sou of thousands attempts and millions upon millions of generations, it happened on a computer two times.
About as close to zero as you can get.
Of course I know you hate when math is turned into reality.
DNA_Jock,
I need to demonstrate that striking an object at a different angle is a different event?
Ok, striking an object at two different angles is two different events. One is one angle, and another is a different angle. Different. No sports huh Jock? Your name is ironic?
That wasn’t very hard.
DNA_Jock,
Now to demonstrate your point you are showing that math can be done wrong and made to look right?
Ok.
Yup, that’s an assertion, not a demonstration.
And, <ggg> I played flanker for Rupert Sheldrake’s alma mater, thank you for asking.
Interesting. There’s no need to confuse yourself with absurd notions about generations; the probability that a particular lone M&M eventually becomes the UCA of all the M&M’s is 1/N. By symmetry.
So N=99 –> 1000 ‘runs’, or N=1,000 –> ‘1 miilion tries’ means that there is, unsurprisingly, an error in your code. Would you deign to share it with us so we can figure this out?
Naah, my point was that you, phoodoo, can’t tell the difference.
😮
No, so I have the sense not to pretend I know what I’m talking about and, instead, have learned to defer to people who do. You might try doing the same. What the hell makes you think you’re so fucking smart? You haven’t had any classes in this stuff, and you haven’t really studied it on your own either–just consulted a couple of conspiracy theory websites. You just think that whatever you happen to believe must be correct.
It’s nothing but hubris (and of the Trumpian variety to boot!). When you either take some classes in this stuff, or have learned how to make your own atomic clock without doing so, maybe you’ll have some creds. As it is now, you’re just being a wingnut.
walto,
Fair enough, but the wingnut makes a valid point (stopped clocks are right twice a day, ‘n’all), to wit, how does one determine to whom one should defer?
Now, we are all agreed that phoodoo is an egregiously bad example, but there’s still an interesting question here…
As WJM put it, if one lacks the expertise to arbit the truth (assessing evidence for evolution, in his example), then one is merely a cheerleader. [As an aside, WJM divided the world into academic biologists, who obviously have a vested interest in maintaining the Darwinst code of omerta, and mere pom-pom waving cheerleaders, thereby conveniently both ignoring the population of competent people who are not (currently) professional biologists and ignoring people who perform their research in a commercial setting…]
As I see it, individuals generally rely on the halo effect (X was right about probability, so I can trust X on relativity), a web of trust (I trust A, B and C, and they trust X), and consensus (99% of professionals agree with X).
All of these methods are fallible — flawed, even. The halo effect is a famous fallacy, and the expert consensus may be wrong.
What’s a guy to do?
This is where the TSZ experiment has been very useful: it turns out that, while it is difficult to tell whether the expert consensus is correct, it is comparatively easy to spot the wingnuts. Wingnuts stand out in the manner in which they dispute. Dishonesty, lack of precision, failure to address counter-arguments, deflection, equivocation and lame-ass rhetorical gambits are their stock-in-trade. So, with phoodoo, as with Sal, Mung, colewd, J-Mac, and Erik, it’s the failure to engage that is a dead giveaway.
Mung stands out in this bunch as being the only one smart enough to realize that he should never attempt to engage.
Gregory, OTOH, is pure performance art. I miss Gregory.
.
Bu does it represent some reality?
Allan says energy has to go somewhere, but he’s not sure where.
Oh, and if you’ve never played sports you can forget about ever becoming a fighter jockey, or camel jockey.
I don’t think it’s that hard, actually. If you want to claim that the scientific community, as represented by the big journals, prestigious departments, etc. Is wrong about some basic matter, you need one or more big, repeatable experiments or a much more elegant theory. If you can’t deliver, it’s just hot air.
It can be done-widely accepted theories have been junked. But it can’t be done just by what wingnuts take to be ‘calling bullshit.’ This is all in Kuhn, btw.
But it can be done by wing nuts who say wait a second, I don’t think the Hafele-Keating experiment really worked, even though practically the entire internet claimed it did.
And it can be done by wing nuts who say, I don’t think there is really as much evidence for Darwinian evolution as all these textbooks, and famous selling authors, and every forum on the internet claims, I think I will remain skeptical and do some of my own thought and investigating.
But a skeptic of course would never do that.
And striking an object at a different angle is a different event. And needing 1.5-5 million generations for a population as small as 1000 is the same as never. It means a new mutation, in a population of 2000 humans, would never, ever ever fix. Does DNA like that math?
Even wing nuts know this. A skeptic wouldn’t know that.
And changing a plants DNA, so that you spray more pesticide on it is not good for humans. But a skeptic would never know that…
And I never said I could overthrow relativity, I said don’t believe everything you read. To a skeptic, that’s being a wing nut.
No, actually it can’t. Maybe you could convince your wife or your kids (assuming they know as little about science as you do), but that’s about it. It’s just hollered wingnuttery.
Or as you, as you admit? The only difference being, according to you, is that you let others think for you.
Precisely. But when that ‘ludicrous’ idea is FIRST proposed, one suspends judgement. The difference between the wingnuts and the visionaries, is that the latter follow though, as you described. That’s how one tells the difference.
phoodoo differs from, say, Peter Mitchell in this regard.