ElasticCollision

Crikey, so for asking a question and pointing out how very unhelpful someone is being in answering it, I get negative reputation.

Doubt I'll be using this site much more now, awful.

And of what use is it to know this if it has changed.

But this goes back to what i said in post(4) about the large hadron collider.

-Not answering my question.

-Asking questions without a question mark.

-Asking questions before answering mine.

-Not explaining what "it" is.

-Referring back to something which hadn't solved anything anyway.

-Causing the entire conversation to go in circles.

Good day to you Sir.

I agree with you,it's ElasticCollision you need to convince.And you don't know it's momentum after point B.

Firstly you're looking at it the wrong way. You don't need to convince me, you need to try and educate me. I'm not saying I don't believe the Heisenberg principle, I'm saying that I don't understand how the idea I have put forward wouldn't work.

I get that detecting an electron changes it's path. But if you manage to eventually detect one that goes through point A and then point B, despite it's change in path, you will have still found it's exact position for that incredibly brief period of time and you could use the time taken for it to move from point A to point B to infer it's speed.

No,the double slit experiment produces the same result with electrons.

And all sub atomic particles,atoms and some molecules such as Buckyballs.

In any case, you've gone way off subject.

The double slit experiment,proves that the electron does not simply go from point A to point B.

You're confusing electrons with photons.

And so what is the size of an electron? And how exactly do you build an apparatus with an opening of that size?

It's very easy to propose experiments that are impossible to perform in practice.

If the size of an electron is unknown, then it seems my original question could have been cleared up extremely quickly.

Are you sure the electron is exactly where you measured it to be? Especially when you repeat the experiment and you get a different answer?

How can you be uncertain? if you are measuring an area that is only the size of an electron, then if the electron is anywhere other than in the path of the detector, it will not be detected.

You get a different number because there is an inherent uncertainty in the value. Electrons are not footballs, so you can't think of them as such.

Right, I wasn't directly thinking of them as such, it was just an analogy.

And I don't see what is uncertain: If you have detected an electron within the maximum space an electron can fill, at two points, then how have you not detected both it's position and momentum with certainty?

What's better than speed which you like to have continuous measurement for, you can I guess measure velocity instead, which is the change in position over time, but an electorn may not always travel in a straight line, or a predictable manner.

But I don't understand how you get a different "number" each time. Whatever that number even represents still hasn't been explained to me.

If electrons were the size of footballs and you had a device measuring an area the size of a football in two points, whether it moved through point A and point B in a straight line or in a wave motion, wouldn't you still get a precise reading of it's position and momentum/speed/velocity?

Are you sure you aren't confusing "speed" for "momentum"? Because the word "momentum" comes up in quantum mechanics almost infinitely more than "speed", and it doesn't mean the same thing as speed. "Speed" is almost meaningless in quantum mechanics, because particles are naturally in a state of superposition, which means they can occupy all possible states at once, and when you measure an electron, all you have is the measurement, you don't actually see it traveling distance over time.

I need a better answer to my original question before I can start thinking about this.

You get a number, but you don't really know how that reflects the reality of what the position and momentum were. If you did a series of measurements on an identically prepared sample, the numbers would not be the same.

Seems I'm getting a bit out of my depth, but as I'm fascinated I can't help but ask: What number do you get? what does it represent? and why doesn't it reflect the reality?

Point B will be at different places each time,each electron will travel away from point A in a different direction,because it was interfered with at point A.

You cannot predict where point B will be.You can only say where point B is after the event.

I see. But in theory, could you not fire hundreds of electrons from a set point A to a set point B, and wait for one which happens to pass through A and B (given that A and B are both measuring an area the size of only one electron), allowing you to know that one particular electron's position and speed with certainty.

The electron does not behave like a single point like object,it behaves like a wave function,therefore each electron will behave differently when detected at point A,point B will be different each time.

I'm still not sure I completely understand. It will be different at point B from point A in what way?

I think what you will find is that even if such a device were possible, if you measured an ensemble of identically prepared electrons you would get a range of answers, because the position of an electron is not well-defined.

I'm not sure I understand. If the same electrons were detected at both point A and point B, their position and speed will have been defined with certainty, wouldn't they?

After Obama won it, I think it lost a lot of credibility. Now it has just become meaningless in my mind. The EU have done nothing to create peace in Europe.

Just look at the situation in Greece, Spain, Germany, Italy, etc.

I suppose that you could say that for a fleeting moment in time the Large Hadron Collider at CERN,does what you are asking.

But then, if it does, doesn't that disproved Heisenberg's principle, because it proves that you can know both it's speed and location precisely at the same time, as long as the device you are measuring with is accurate enough?

you cannot predict at which point it will arrive at the detector(x=10,y=?,z=?),or if it misses the detector then (x=?,y=?,z=?).

I see. Would it not be possible to simply use a detector which only measures a space that is the size of one electron though?

Surely that would allow it's position to be known with accuracy, as well as it's speed?

If you are able to measure the time taken for an electron to move from point A to point B in order to find it's speed, surely you also know it's location at both point A and point B, as these points are where you are measuring the electron passing through.

As Timo has stated it is the coupling strength of the particle to the Higgs field, ie. how strongly the particle interacts with the scalar Higgs field, which supposedly determines the mass of the particle. Not the strength of the Higgs field, which would have a constant value.

Different quarks, if the superstring representation is valid, would have differing vibrational harmonics which would affect their coupling strength to give different masses for the quarks. Again, assuming the validity of superstring theory.

There is also a Machian theory of mass which is due to the local, causal distribution of mass-energy, as I don't think the Higgs boson has been 100% identified yet. And since scalar fields can couple with gravity, the cause of mass could even be a combination of Higgs and Mach mechanisms.

Is there some sort of theory as to how the strings get these different vibrational harmonics though?

To me the whole notion that one particle gives the other particles mass is an oxymoron, and has been for some thirty years. You can really only say

that 'there exists certain relations among the particle masses', since particle mass relations are dimensionless ratios. You might be able to link the

particle masses to some other dimensional quantity, like a natural unit of time and say that that quantity sets the scale of mass relations. People

used to try to link the Electron mass to its charge, but charge is a scale invariant quantity and mass is a scale quantity, so it's patently obvious that

that is a no-go proposition.

 

The whole notion isn't well thought out.

I thought the Higgs boson was massless. My understanding of it was that quarks and Higgs boson are both massless, and their combination "creates" mass.

I recently read about the fate of the Sun, and therefore the Earth, in 5billion years and began to wonder if humanity would survive.

Of course in the meantime there are other things which could spell our extinction, such as the Moon leaving the influence of Earth's gravity, the Milky Way/Andromeda collision and much sooner; global warming.

However, I imagined what exactly humans could do to survive the Sun's red giant phase, imagining we had survived these other problems.

I was surprised and fascinated to come across a paper that actually looks into ideas about this very thing. I was mostly surprised because I wouldn't have expected science to begin thinking about such a far off problem.

The paper: http://arxiv.org/pdf/0811.4052.pdf

As a short summary of the paper, for those who don't wish to read it all:

There are two plans,

1) "we propose to construct some kind of parasol to shadow Earth" however this will only shield the Earth for an extra 5billion years.

2) In order to survive further than 5billion years: "shift Earth into the Kuiper Belt (50 AU) by means of the swing-by technique whereby the overwhelming part of the gravitational energy needed will be transferred from the orbit of Jupiter and Saturn."

I just wanted to know what people's thoughts on these plans are. Of course the swing-by technique holds many problems and dangers, but with better technology, could this be plausible?

And has anyone else got their own theories for things that could be done to survive the red giant phase?

Because the atmosphere contains the clouds that be a very good example and so the clouds be a vapor and it transforms into water a liquid and be called rain though

So that be the only reason for the presence of water

TROLL IN THE DUNGEON!

I saw this myself very recently. This should thankfully aid human health exponentially, as ethics groups who stopped stem cells in their tracks due to their source being fetuses can no longer make such claims.

Any line source will drop off as 1/r because of the geometry — the surface area increases with distance. Point sources drop off as 1/r^2.

I think I understand, but not entirely. I can't see an answer to my question in that.

I'm not entirely sure whether EM is a point or a line source (I think it is a point source, but I'm not 100%), but whichever it is, if it gets weaker through a vacuum, shouldn't that be evidence for some sort of aether that it is passing through and losing energy to?

Or am I entirely wrong, and EM doesn't lose energy in a vacuum?

The fluorescent bulb is lit because the potential difference across the bulb is large enough; the source is the radiation from the transmission lines. The effect will diminish with distance because for a line or point source, that's what happens.

Why does the effect diminish? Wouldn't this be evidence that it is passing through a medium and losing energy? Or does this effect only take place within an atmosphere as the radiation is absorbed by, for example, air?

It means theoretically, even if matter can't travel faster than light, it can get from point A to point B faster than light because there's no limit on how fast the fabric of space itself can stretch.

I see. This must have all kinds of implications regarding possible time travel.