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a reply to: delbertlarson

Hi Arbitrageur - great to see you back. There were several things that have come up in the past two and a half weeks I thought you might respond to. blackcrowe asked for an answer to your Oct. 19 questions on the top of page 373.

Thanks delbertlarson;

That's cool of you.

a reply to: Arbitrageur

Thanks for the answers.

The first part of your question. I answered because it was there. The alleged events and rumours in the link seemed more like "high weirdness". And. I don't tend to get myself involved in that sort of topic usually. But. Something unusual certainly seems to have occurred. I'm not saying "high weirdness" though.

Asphalt roads apparently don't have nearly the compression or tensile properties that railroad tracks have

This is where i'm qualified in my job. Highway construction.

Asphalt is basically heated up sand with some added bitumen. It's not far off being glass really.

That is only the top layer though. Underneath is a layer of base tarmac. Which, Although they are 2 layers. They do stick together with the heat, bitumen and pressure from being rolled and vibrated.

These 2 layers sit on top of more layers of different sized compressed stone.

The kerb edge is there. Not for a footway. But. To stop the road from splaying out.

Asphalt is more brittle than tarmac due to it's sandier content and higher temp when being made.

So. An asphalt road would not have as much flex as a tarmac road. But in a quake. It won't make a lot of difference.

So this leaves an interesting question, how does this deal with thermal expansion? Apparently the answer is, sometimes it doesn't, and a number of train derailments every year result from "sun-kinks" which result from distortion of the track when it gets hot. OK so that these "sun-kinks" occur should be no surprise to any physicist or engineer, right? When the track expands too much such that the existing restraints are insufficient to restrain it, the restraints give way and the track distorts. Here's an example of a sun kink from the Iowa DOT website:

But. The story we're looking at (without going back to check) was not going to due to a sun kink.

Although i understand your point. Nowhere to go when it expands. Something has to give.

There are 4 questions you could ask here: 1. Was the correct neutral temperature selected? (temperature where the track is neither under tension or compression) 2. Is the ballast poor? 3. Were there unclipped sleepers? 4. Were there loose ties?

I cannot answer those.

Why that particular shape of distortion looking almost sine-wavy instead of the whole kink just being pushed off to one side? I don't know. Could some spots be anchored better than others? Could there have been some kind of resonance or pattern in the earthquake waves or the type of shaking which contributed to that shape? Again I don't know.

This interested me too.

I did suggest that if the tracks weren't anchored to the ground. But. If they were anchored further apart. if the displacement happened between 2 sets of anchors.(Although i didn't quite put it like that) That the track should have curved off the ground, upwards and not sideways.

And. It is because it's secured to the ground. And, probably the shape of the track too that it shows the sideways shape.

Also. Any chance for the tracks to move upward and take the anchors up too. Would be harder. Due to more pressure on the anchors by the ground compressing around them. Making them tighter secured.

originally posted by: blackcrowe
a reply to: Arbitrageur

Thanks for the answers.

The first part of your question. I answered because it was there. The alleged events and rumours in the link seemed more like "high weirdness". And. I don't tend to get myself involved in that sort of topic usually. But. Something unusual certainly seems to have occurred. I'm not saying "high weirdness" though.

Agreed it's not high weirdness, it's just that the official story makes no sense and nobody will say what really happened. At least one or two ATS members seem to think they know what happened and they say it's not that weird even though they can't say what it is.

This is where i'm qualified in my job. Highway construction.

I suppose that explains why you seemed to have good knowledge about what the video was showing on the road damage.

Asphalt is basically heated up sand with some added bitumen. It's not far off being glass really.

That is only the top layer though. Underneath is a layer of base tarmac. Which, Although they are 2 layers. They do stick together with the heat, bitumen and pressure from being rolled and vibrated.

These 2 layers sit on top of more layers of different sized compressed stone.

The kerb edge is there. Not for a footway. But. To stop the road from splaying out.

Asphalt is more brittle than tarmac due to it's sandier content and higher temp when being made.

So. An asphalt road would not have as much flex as a tarmac road. But in a quake. It won't make a lot of difference.

In the following picture, if you set aside the giant chasm to hell in the middle, and look at the two yellow arrows I drew, I think that supports what you are saying about the asphalt being brittle and if the road stretched (which wasn't exactly the case here), then I expect to see the asphalt surface have gaps in it, like these small cracks or larger.

www.theatlantic.com...


Conversely, under compression, in the NZ video, you could see the asphalt surface "tenting" not unlike taking a flat sheet of paper and pushing the sides together and seeing the middle bulge up, though the asphalt again being brittle cracks when it does that. That's what was seen in the earthquake damage in the video I posted, which to me confirms it's compression, not tension.

But. The story we're looking at (without going back to check) was not going to due to a sun kink.

Had there been no earthquake, there might not have been any sun kink, so I guess you're right from that perspective. However, if you don't consider sun kink being involved in the earthquake event, how do you explain 9 extra meters of track when the ground only moved 4 meters according to one source I read? The only answer I can think of is 4 meters of track due to ground movement from the earthquake, and 5 meters of track added to that when the thermal stress was relieved, which in some sense is at least related to a sun kink, which was my reason for going into that explanation. I hope the people who said physicists were wrong about matter and energy being conserved because 9 extra meters of track appeared were only joking, but it was hard to tell.

I cannot answer those.

Neither can I though I might be able to with better examination. It's interesting to contrast New Zealand Earthquake tracks where the tracks stayed attached to the ties, with these Alaskan earthquake tracks where the tracks became detached from the ties.



Obviously the failure point here is easier to observe, and why do the tracks stay attached to the ties in one earthquake but not the other? Maybe the attachment of these tracks was too weak? Not that the tracks shouldn't have been damaged, but maybe the ties should have stayed attached when they warped if they had better attachments? Thoughts?

I did suggest that if the tracks weren't anchored to the ground.

I'm not a railway engineer but my understanding is the tracks are anchored to the ties, not the ground. Then there's a whole support structure for keeping the ties in place, of which the ballast is a key component and if it's not compacted well enough the ties can move more than they should. But other than being held in place by the compacted ballast, the ties or "sleepers" aren't anchored to the ground as far as I know. I didn't find anything about ground anchors in this:

Track Basics - The Railway Technical Website

But. If they were anchored further apart. if the displacement happened between 2 sets of anchors.(Although i didn't quite put it like that) That the track should have curved off the ground, upwards and not sideways.

Like the Alaska earthquake photo? But the anchors that failed were the ones holding the tracks to the ties, I don't see anything anchored to the ground.

Regarding the wavy shape of the NZ distortion, I didn't mention liquefaction and subsidence because I have no reason to think it was a factor in New Zealand, but you can see it was apparently a factor in this Denali theater sinking far into the ground in the Alaska earthquake.



So that clearly shows if the ground is water-laden or has a high water table the properties of the ground can change drastically during an earthquake. However, I'm not sure how much the properties of the ground can change if it's not wet. Maybe it can happen to a lesser extent, and if so maybe that could be a factor in the curvy shape of the distortion, where maybe the properties of the ground and ballast changed in that area during the quake. Not liquefaction, but maybe something that can happen to drier ground or even the ballast, to change the properties? I'm only speculating, well not completely, because part of the reason ballast works is the stones have irregular shapes which are supposed to "interlock" to some degree, and if you start shaking them, then that interlocking mechanism can't do its job any more, right? They are not that firmly locked, just somewhat from the compaction and settling when the trains go by, but the shaking of an earthquake can disrupt that interlocking, I suppose.

a reply to: Arbitrageur

All of your railway examples are interesting but the common obfuscation they all share is that they each convey only a subset of the available information. Verschickt(er) mentioned André-Marie Ampère which might make some interesting homework for someone. This thread reminds me of that short story the P&TP.

a reply to: Arbitrageur

Thanks.

First. I wish i had read a little about rail construction before assuming there would be piles or something at points securing the tracks to the ground somehow. Read it now. It's very similar to road construction.

The ballast is what is called sub base on roads. This is what the surface lays on. Like with tracks. It is stone. So, naturally good for drainage. Locks together and is flexible compared to a track or asphalt surface.

Some differences are that under roads. There are sewers and surface water drainage, along with services (gas/elec/water/comms) which can run along or across or any other.

The first pic in your above reply. This shows how thin the surface is. You can also see how the sheet of road spans across the "giant chasm to hell". This becomes a real problem when there is water erosion. Usually due to a leak. It can wash away the grit and smaller stones, to bigger stones from the sub base. In worst cases. A void can form. Usually noticed by a depression. Like in this quote.

I didn't mention liquefaction and subsidence because I have no reason to think it was a factor in New Zealand

I also agree that the NZ roads look compressed.

I dismissed the sun kink based on the time of year of the quake. Unless i've misunderstood it.

But the sun kink at least allows for some explanation. As it seems stranger for it not to be factor possibly.

However, if you don't consider sun kink being involved in the earthquake event, how do you explain 9 extra meters of track when the ground only moved 4 meters according to one source I read? The only answer I can think of is 4 meters of track due to ground movement from the earthquake, and 5 meters of track added to that when the thermal stress was relieved, which in some sense is at least related to a sun kink, which was my reason for going into that explanation.

I know the track can be measured to be 9 meters. So we can be more sure of this figure.

I would more question the accuracy of the 4 meters ground movement. And suggest it was more. But i do not know the means and accuracy of the 4 meters result. Not saying it's the full 9 meters.

If it is accurate. Then 5 added meters seems beyond possible.

But there was a lot of force in the area of the tracks.

This might not be relevant. When the ballast was made. It was compressed. Downwards.

The quake wave would have been upwards and outwards. Together with a lack of an equivalent kerb type edge. The sleepers would have more room to wriggle and move through the vibrating moving ballast. It would be similar to swimming through the stones.

The pic with the tracks popped off the sleepers. Could be several reasons. My choice would be that the ties snapped and were flung/shaken out. Maybe they were missing. The sleepers haven't moved. It seems they would have broken without much effort. Weak as you suggested. Or even bad materials/workmanship.

a reply to: Arbitrageur

On how much it would take to pay off scientists to keep them quiet, I mentioned I didn't think they'd do it for money. But by that I meant personal remuneration. If there was a fear that the whole operation would be shut down because of possible bad press about something embarrassing, people might stay quiet. In a sense that is money too, but in science it is more than just that, as the whole enterprise is threatened. Our friends, colleagues, and their families will be hurt deeply. Also, we do what we do because of a deeper calling, and to see it all end over something stupid is something that might be kept quiet. Everything we've worked on for decades can be gone - like the SSC.

Thanks for more on the tracks. You are right that I didn't watch the video - I just speculated.

I recognize that at one time we thought protons and neutrons were fundamental particles and didn't know their composition. I don't really follow your explanation because the concept of "part of an electron" is foreign to me. I can't deny that like the proton and neutron we may someday discover that electrons too can have "parts", but I don't really understand your proposal here. So if the electron splits into two parts to go through the two slits then you can have half an electron (two halves)? Then with three slits, the electron could split into thirds, and so on so it's infinitely divisible into as many parts as there are slits? I'm not sure how then it's still a particle, which seems more like going back to the wave description. Now perhaps if I could see some experimental evidence of "half an electron" which went through one of the slits, I might be persuaded, but it's not apparent to me at all that's what is happening in the two slit experiment.

My view of quantum nature is that entities are essentially continuous bodies with an underlying (carrier) wave and an overlapping envelope. They have a one-ness in that when they exchange momentum with other entities they act as individual entities despite their internal continuous nature: their wave-function, which is the square root of their density, collapses when they exchange momentum. When I say half the electron goes through each slit I do not mean sub-particles. Rather I mean half of this continuum material that makes it up. The collapse rule I propose is that a collapse must occur to a size dx = hbar/2dp whenever a momentum exchange of dp is required, OR, a collapse occurs to the entire region where no collapse is required. Yes, it would collapse to as many parts as there are slits. The proportion that collapses to each slit is determined by the wavefunction magnitude at that slit before collapse. And yes, this is a return to the wave description, except for the one-ness and the quantum collapse law. (It is not a full return to the classical wave description - quantum effects are clearly present!) To me, this is a very simple underlying proposal that eliminates all of the mysteries.

The only reason my simple proposal can't be accepted is because of the requirement of instantaneity of the collapse, since that violates relativity. But absolute theory will allow instantaneity and it is also completely consistent with experiment, so we really shouldn't be hung up on advancing science just because relativity is considered so beautiful and elegant.

originally posted by: delbertlarson
a reply to: Arbitrageur

On how much it would take to pay off scientists to keep them quiet, I mentioned I didn't think they'd do it for money. But by that I meant personal remuneration.

There are some things I couldn't be paid any amount to keep quiet about like maybe mass genocide or something which should not be kept secret under any circumstances. But I think for more mundane things I have a price tag to keep my mouth shut and I suspect most people do. This is one of the hints Zaphod gave for what really happened though it's cryptic since if it was really that mundane, you would think they could talk about it:

National Solar Observatory, USPS office in Sunspot, NM evacuated for 'safety reasons'

It's something, as I said, that is utterly mundane, but not something you'd think of. In this case you have to go outside the box. Way outside it.

Plus if it's what some have suggested, the employees there might also get the "keep quiet for the sake of national security" speech in addition to cash payment to do same, so that might make it a bit more than money but with the real events unconfirmed we can't confirm that's a factor.

If there was a fear that the whole operation would be shut down because of possible bad press about something embarrassing, people might stay quiet. In a sense that is money too, but in science it is more than just that, as the whole enterprise is threatened. Our friends, colleagues, and their families will be hurt deeply.

That reminded me about an article I read on nearly that very subject relating to particle physics. It's about a fictional TV episode of the Big Bang series but the blogging physicist notes they often get the science right on that show because they have a good science consultant, and this is really a bit scary and along the lines of what you just said:

The Big Bang Theory and the Death of SUSY

LEONARD: Look, I know I screwed up, but it was only one interview.
How much damage could it have caused?

Ms. DAVIS: Would you like for me to read you the e-mails from donors asking why are they giving us money if physics is a dead end?

LEONARD: I didn’t say it was a dead end. I just said that I was worried it might be.

Ms. DAVIS: So if I just said I was worried you might not have a job next week, how would you feel?

LEONARD: Light-headed, and glad you asked me to sit down. Okay, just tell me what I can do.

Ms. DAVIS: I’m gonna need you to make a statement saying that you misspoke, and that you’re confident the physics community is close to a major breakthrough.

LEONARD: You want me to lie.

Ms. DAVIS: Look, Dr. Hofstadter, I’m counting on you. I think that you are the smartest physicist at this university.

LEONARD: Really?

Ms. DAVIS: See? Lies. They’re not that hard.

That last line is pretty funny but the rest is a little too close to the truth, at least about that branch of physics it seems. I mean the Higgs was found, and not much else of interest, so what now? Just increase the energy some more and keep building bigger colliders and see if something else shows up? I guess dark matter searches can continue exploring additional parameter spaces so that might be a branch of particle physics where something new turns up in an unexplored parameter space, but as for SUSY, is it really dead?

My view of quantum nature is that entities are essentially continuous bodies with an underlying (carrier) wave and an overlapping envelope. They have a one-ness in that when they exchange momentum with other entities they act as individual entities despite their internal continuous nature: their wave-function, which is the square root of their density, collapses when they exchange momentum. When I say half the electron goes through each slit I do not mean sub-particles. Rather I mean half of this continuum material that makes it up.

But doesn't the wave-function say the electron also has a chance of going through neither slit? So if you have half going through one slit, and another half going through the other slit, and you also have some probability it will go through neither slit, doesn't that make it add up to more than 100%? Or when you said half you didn't really mean half, but whatever is calculated from the wave function?

originally posted by: blackcrowe
But the sun kink at least allows for some explanation. As it seems stranger for it not to be factor possibly.
I know the track can be measured to be 9 meters. So we can be more sure of this figure.

I would more question the accuracy of the 4 meters ground movement. And suggest it was more. But i do not know the means and accuracy of the 4 meters result. Not saying it's the full 9 meters.

If it is accurate. Then 5 added meters seems beyond possible.

It's always wise to question the accuracy of measurements like that, and am not sure about the 4 meters ground movement being accurate and that probably varied location, so at best it's some sort of approximate number for a particular location. Whether 5 meters of thermal stress is possible, I don't know, but doing some quick calculations, the design limits I think are typically 1 part in 1800 expansion for an 80 degree temperature increase (above the neutral temperature at which the track is unstressed). So if it was near the high end of that then to have 5 meters of expansion would take 9km of track. I know CWR got rid of the vast majority of the expansion joints, but I don't know if they might still have expansion joints at far less frequent intervals, so maybe 9km without any expansion joints at all would be a bit much as you suggest, though perhaps not impossible. As long as the temperature increase doesn't exceed 80 degrees and everything else is sound, the track is supposed to be able to withstand that kind of 1 part in 1800 thermal stress, in either direction (hot or cold).

The quake wave would have been upwards and outwards. Together with a lack of an equivalent kerb type edge. The sleepers would have more room to wriggle and move through the vibrating moving ballast. It would be similar to swimming through the stones.

Yes sort of, though my thoughts don't require specifics on the earthquake waves, rather just the shaking of the ballast is enough to disrupt the locking mechanism it normally employs, rendering it far less effective in restraining lateral movement of the ties or sleepers during the earthquake.

The pic with the tracks popped off the sleepers. Could be several reasons. My choice would be that the ties snapped and were flung/shaken out. Maybe they were missing. The sleepers haven't moved. It seems they would have broken without much effort. Weak as you suggested. Or even bad materials/workmanship.

I'm thinking something like weak fasteners, but one other possibility I didn't mention earlier because I don't see ice in the photo, but if the ties were frozen into the ground then even strong attachments could pop loose with the high rail stress. I wasn't looking for it but coincidentally I happened to run across this old image of a distorted track with the ties still attached, so they don't have to become separated under extreme stress.

That's from an old "In Search of" television episode on hurricanes, showing the aftermath of hurricane Camille.

a reply to: Arbitrageur

If it was seasonal differences you meant.

September Weather It's not that New Zealand hibernates in its winter months (far from it), but in September, the first month of spring, there is so much activity in terms of festivals and events, that you may find it hard to choose the most appealing. The weather in September is typical of spring – the days start to get longer, the sun has a bit more heat and there's still a reasonable amount of water around (rain and snowmelt). So what can you expect? On the North Island, temperatures between 7 to 17°C and on the South Island, anything from 5 to 17°C. Pack for 'four seasons' in a day and you won't go far wrong!

From here

I know there are exceptions too.

It's always wise to question the accuracy of measurements like that, and am not sure about the 4 meters ground movement being accurate and that probably varied location, so at best it's some sort of approximate number for a particular location. Whether 5 meters of thermal stress is possible, I don't know, but doing some quick calculations, the design limits I think are typically 1 part in 1800 expansion for an 80 degree temperature increase (above the neutral temperature at which the track is unstressed). So if it was near the high end of that then to have 5 meters of expansion would take 9km of track. I know CWR got rid of the vast majority of the expansion joints, but I don't know if they might still have expansion joints at far less frequent intervals, so maybe 9km without any expansion joints at all would be a bit much as you suggest, though perhaps not impossible. As long as the temperature increase doesn't exceed 80 degrees and everything else is sound, the track is supposed to be able to withstand that kind of 1 part in 1800 thermal stress, in either direction (hot or cold).

I would rather prefer to see less than 5m of expansion to make it easier to account for. But. Even if it was less. It would still need to be accounted for.

I don't think the track temp would have been an issue. Except where the stress/distortion was.

Yes sort of, though my thoughts don't require specifics on the earthquake waves, rather just the shaking of the ballast is enough to disrupt the locking mechanism it normally employs, rendering it far less effective in restraining lateral movement of the ties or sleepers during the earthquake.

Everything about the ballast is made using downward vibration. It is only truly stable after it cant move any more from downward vibration. It is sat on the hard ground. Pushed down by gravity. And that is enough for normal conditions. The locking of the stones is because all i that material together is unnatural. The locking stops short of what should naturally happen.The vibration should settle small on bottom. Biggest on top. But an opposite upward vibration would exploit the part finished, only works properly in one direction ballast.

Although, as you say. Shaking might be enough. And i might see direction as more important. Over thinking it.

That last pic. Hurricane Camille. They're fastened properly.

Maybe ice could've contributed to the missing ties. Not only locking the sleepers down by freezing. Would perhaps also make the ties more brittle. Which exposed a weakness. Although they were probably within a standard quality. The quake exceeded the standard.

We don't get quakes here. So. This has been interesting. And i hope i never experience one. That power/energy is devastating.

originally posted by: Arbitrageur
The Big Bang Theory and the Death of SUSY

Ms. DAVIS: I’m gonna need you to make a statement saying that you misspoke, and that you’re confident the physics community is close to a major breakthrough.

In a slight variation of that television script, this particle physicist, Harry Cliff, says we might be on the edge of a major breakthrough, though he doesn't say he's confident about it, he uses plenty of cautions that while the data appears to violate the standard model, it may turn out that it doesn't violate the standard model after all. More data and analysis should provide the answer either way.

Beyond the Higgs: What's Next for the LHC? - with Harry Cliff


This is a review of the progress so far in trying to answer the question if that data really breaks the standard model or not, from September 2018.

Review of Lepton Universality tests in B decays

...it is of paramount importance to confirm or refute these hints of LU violation promptly. Both the Belle-II and LHCb experiments will be in an ideal position to provide additional information by significantly reducing the uncertainties on the LU observables already studied and by measuring new observables that will further constrain NP models. The present situation should thus evolve rapidly with the combined efforts of experimentalists and theorists, and has the potential to provide very exciting news in the coming years.

So, the answer didn't come as quickly as Harry Cliff hoped, and more analysis is needed.

originally posted by: blackcrowe
I would rather prefer to see less than 5m of expansion to make it easier to account for. But. Even if it was less. It would still need to be accounted for.

I'm not satisfied either that we know where 9 meters of extra track came from. 4 meters maybe, but I don't know about the other 5 meters.

But if you think 5 meters is a lot, an interesting factoid mentioned in the above video is that the LHC tube (inside the long thing painted blue below) gets 30 meters longer when they turn it off! Then it shrinks 30 meters when they turn it back on, and still has to be able to get two protons beams to hit each other which requires very precise alignment. Cliff notes the engineering challenges to do this successfully are astounding.

a reply to: Arbitrageur

My real problem here is. I don't believe sun kink was involved. What does that leave? I can only think. Dynamics of the quake. And, i don't know how these would work.

But. we know there was at least 4m displacement. Which creates stress. Stress into heat. So. Is it possible that the dynamics caused enough stress heating as the energy moved through the track over a possible 9km distance. But having a distortion point. Could this mean the track heated to allow expansion from only 4.5km each side of the distortion?

the Higgs was found, and not much else of interest, so what now?

One thing HEP can look for now is, of course, preons. But I won't hold my breath waiting to be discovered. I do try. A little. Mostly here, and one talk a year at Brookhaven to a dozen or so people.

But doesn't the wave-function say the electron also has a chance of going through neither slit? So if you have half going through one slit, and another half going through the other slit, and you also have some probability it will go through neither slit, doesn't that make it add up to more than 100%? Or when you said half you didn't really mean half, but whatever is calculated from the wave function?

Specifically, when an electron, or photon, or neutron impinges upon a wall containing two slits, right before reaching that wall there will be a wavefunction along the plane parallel to that wall. When that wavefunction reaches the wall, one of two things happen: 1) It hits the wall, and the collapse occurs to a single point of size dx = hbar/2dp, where dp is the momentum exchanged with the wall. Or 2) it passes through both slits, with the collapse occurring to the region of both slits. If the wavefunction is such that it is equal in front of each slit before the collapse, and if the particle doesn't collapse on the wall, it will collapse so that half of the particle goes through each slit.

Generally, the square of the wavefunction is the density of of the particle. As it propagates a wavefunction of a particle may encounter wavefunctions of other particles. The encounter may require a momentum exchange over a portion, or all, of the regions of the original wavefunction. If the collapse occurs where a momentum exchange is required, the collapse will result in a new wavefunction of size dx = hbar/2dp, where dp is the momentum exchanged. If the collapse occurs where no momentum exchange is required, the collapse will result in a new wavefunction that occupies the whole of that region where no momentum exchange is required, and the new wavefunction will be proportional to, and larger than, the pre-collapse wavefunction in the entire region where no collapse is required. It is larger, since it collapsed way from the regions where collapse was required.

Basically, when a wavefunction encounters an obstacle it must either collapse to a spot on that obstacle or rearrange itself to get out of the way.

Let me know if there is still some lack of clarity and I will continue to try to explain this further. I have believed everything makes sense for close to 40 years now, and I believe this is the answer to the OP. mbkennel and I had a discussion about this on this thread starting on page 287. Those were my first posts here on ATS.

a reply to: delbertlarson

Could the 2 slit experiment be done with 15 slits and the same phenomena will happen?

Does it mean. Every point of/on a wave. Is a point of a wave?

a reply to: blackcrowe

Yes, if there are more slits the wavefunction will collapse to all of them if it doesn't collapse to the first wall. But then you will get a different type of interference pattern at the second wall.

An amusing anecdote: The one time I got less than an A in my undergraduate level courses was partly because of an optics lab. We were supposed to carefully blacken a small window with some substance, it might have been aquadag, and then shine a laser on it and observe and calculate the interference pattern. Well, as a partier at the time (college days) I was in a bit of a hurry that day and hence sloppy. So there were several holes in the black surface. Going through the results in the following days I worked to derive how the holes contributed to the interference results, as we didn't have the usual clean two slit results - we had some spurious peaks here and there. I was able to calculate where they all would be by assuming the relevant portions of the light went through both the slits and various holes. I was pretty excited about the results, since it clearly showed how the holes contributed to the observations. But the professor wanted quality in the experimental technique, not a good analysis of a sloppy experiment, so I was down-graded.

It's too bad, really. Sometimes when you do something unintentional you can get new and interesting results! If you always do it the same old way, you get the same thing over and over again. Where's the learning in that? Of course all work should be verified (which is a topic for another thread) but once it has been verified, say 1000 times, might it not be better to try something else? At least once?

a reply to: delbertlarson

Thanks.

That's a great story. And i agree with changing something. Even unintentionally, can offer new and unexpected results. And. That's learning.

I think marking you down was a bit harsh. Maybe it was worth it just for the "something different" value.

You have a story about The only time you got less than "A".

Sorry. I never got an "A" to tell a story about.

a reply to: Arbitrageur

Could the energy of the wave radiate outward from point x. Along the tracks and away from x. Causing the expansion which would then be resisted by another cooler part of the track. Then having created extra length. Cause an opposite reaction to send the energy back towards point x. Now having 2 waves of energy on a collision course at point x.

This is only guesswork now.

originally posted by: delbertlarson
One thing HEP can look for now is, of course, preons. But I won't hold my breath waiting to be discovered. I do try. A little. Mostly here, and one talk a year at Brookhaven to a dozen or so people.

I don't know how experimental physicists decide which ideas of theoretical physicists to test. Even in the famous case of teams trying to observe eclipses trying to test relativity, what motivated them to do that? One team even got captured with their telescopes and eclipse observing equipment and were charged with being spies during the war.

Maybe you need to make some friends at CERN to get some of them interested in searching the data for your predictions, since a lot of other theories have bombed out, maybe they haven't even tested yours yet...probably not, right?

Specifically, when an electron, or photon, or neutron impinges upon a wall containing two slits, right before reaching that wall there will be a wavefunction along the plane parallel to that wall. When that wavefunction reaches the wall, one of two things happen: 1) It hits the wall, and the collapse occurs to a single point of size dx = hbar/2dp, where dp is the momentum exchanged with the wall. Or 2) it passes through both slits, with the collapse occurring to the region of both slits. If the wavefunction is such that it is equal in front of each slit before the collapse, and if the particle doesn't collapse on the wall, it will collapse so that half of the particle goes through each slit...

Let me know if there is still some lack of clarity and I will continue to try to explain this further. I have believed everything makes sense for close to 40 years now, and I believe this is the answer to the OP. mbkennel and I had a discussion about this on this thread starting on page 287.

I think if you try to make a "realist" interpretation of events during the quantum eraser experiment, meaning you have absolute time, causality such that events happen after the events that caused them, you will run into some problems, but if you've already written an explanation of this, no need to write it again, you can point me to it and I'll read what you've already written. Or if you haven't explained that yet maybe you can explain it here how a realistic interpretation shows it's not really re-writing the past. The first 10 minutes of this video explains the experiment I'm talking about, one being done in 1999 and some other variations since.

How the Quantum Eraser Rewrites the Past

Causality is meant to move in one direction: forward. But the Quantum Eraser experiment seems to reverse causality. How and why can this happen and what are the implications of this experiment on how we understand Quantum Mechanics and our greater universe?

I think the catchy "click-bait" title about rewriting the past is more or less what results from trying to interpret the experiment a certain way, but with the quantum mechanics interpretations taught in textbooks like Copenhagen, I don't think the experiment shows the past is being re-written, it's just a predicted feature of quantum mechanics.

I didn't include this version of the double slit experiment in my list of non-intuitive quantum mechanics for Daniel since he's apparently struggling with simpler concepts, and this experiment is somewhat complicated, the results of this experiment seem to challenge human intuition with any possible explanation I can think of.

A Delayed Choice Quantum Eraser
arxiv.org...

originally posted by: blackcrowe
a reply to: Arbitrageur

Could the energy of the wave radiate outward from point x. Along the tracks and away from x. Causing the expansion which would then be resisted by another cooler part of the track. Then having created extra length. Cause an opposite reaction to send the energy back towards point x. Now having 2 waves of energy on a collision course at point x.

This is only guesswork now.

As I agreed, questioning the data is a sound approach. Maybe the extra track was 9 meters but was the ground movement really only 4 meters?

If the heat-related thermal expansion idea bombs out and maybe you're right that it does, I'm not able to find any other realistic stretching mechanisms to account for that much extra length of track. The waves from the earthquake might heat the track a tiny bit but I think probably not much. You said you haven't experienced earthquakes I think...I have and they don't last long, which is why I think any heating of track from the earthquake waves is going to be very limited due to the short duration.

Ground movement in a stretching direction might stretch the track, but as we already determined, the opposite thing happened here, ground movement caused compression rather than tension in the track.

Here's a picture from the same earthquake, showing a storm sewer popped up from the road, ever seen that before? I think I know what caused that, maybe.

Storm drain pushed up through road

a reply to: delbertlarson

If you played a game of double up with the slits.

1 slit = 1 particle. Of a size you have math for. I'll call 1.

2 slits = 2 particles. Not half the size of 1?

4 slits = 4 particles. Now true 4th's. Not 4th's size though.

8 slits blah blah blah. Why are 8. 16 or even a million particles all the same size of 1?

a reply to: Arbitrageur

Could the energy of the wave radiate outward from point x (the distortion). Along the tracks and away from x. Causing the expansion which would then be resisted further along the track. Then having already created extra length. Cause an opposite reaction. Another possible wave created. Radiates out from that point along the tacks. 1 half of the wave now moving away from original point x. The other half, back towards point x. Same thing happening on other side of point x. That's 2 waves of energy on a collision course at point x.

could double heating from the 2 waves do it?

I never liked the 5m. And still question it. But putting the distortion point in the middle halved it for me. So, its 2.5m. It's still 5m. But looks better.

This is only guesswork now.

a reply to: Arbitrageur

Never seen anything like that storm drain before.

Although i have quals for working on roads.You are adding things i no nothing about into the equation.

You can't rely on my answers to these type of questions.

But. If you're happy to carry on doing it.

I'm happy carrying on with it too.

That drain has at least 2 big pipes running length ways along the road attached to it. The pipework is bedded on a stone bed. Then, surrounded by stone.

I GUESS the whole length of pipework was lifted as the stone surrounding worked it's way underneath. Lifting the inspection chamber with it.