new scientist

[owl37400]

Cup of tea, anyone? -State which direction you want it stirred, clockwise or anticlockwise!

careful, you might kick off a milk-before tea tastes better than tea-before milk debate.

Scientific quiz:
Which will result in the cooler cup of tea -
a) Tea in cup, then milk straight in cup, then leave for five minutes
b) Tea in cup, then wait five minutes, then put in milk.
Assuming milk and tea are the same temperature in each case, of course.

 

[Neil]

b) - bigger temp differential twixt tea + air so more heat loss during 5 mins - so put the milk in and leave it for 5 - voila, hotter tea.


erm...I think

 

[ben556473]

Firstly the reason I wrote 'no comment' to brizonbiovizier was because what he wrote showed his lack of understanding ( he was telling me that I was talking about a different experiment, which is an obsurd way to argue.) This was kindly highlighted by Oedipus. What I said is not mysticism, it is a common discussion among physicists.

 

[Paul Ranson]

Can you provide a link?

Paul

 

[owl37400]

Firstly the reason I wrote 'no comment' to brizonbiovizier was because what he wrote showed his lack of understanding ( he was telling me that I was talking about a different experiment, which is an obsurd way to argue.) This was kindly highlighted by Oedipus. What I said is not mysticism, it is a common discussion among physicists.

Perhaps either you or oedipus could explain more clearly exactly why you think the young's slits experiment is relevant to a discussion about directional cables.

I think it is this bit of your post that we find a bit "mystical":

This would logically prove a consciousness of each other by seperate particles of light. These are separated by time and space yet know where the other has gone previously and alter there course accordingly to form the light and dark banding.

As far as I remember from my secondary-school physics, all that this experiment demonstrates is that light can be considered to have either particle-like or wave-like properties. As I understand it the waves can be interpretated as fluctuations in the probability of a particle being in a certain place at a certain time (although I have to say it was quite a long time ago that I studied this so someone may correct me).

Anyway, the point is that the photons don't "alter their course" due to a "consciousness" of each other. The banding, as I understand it, is simply a phenomenon similar to that of audible peaks and troughs caused by standing waves experienced in certain acoustical situations.

The photons pass through the slits and their course is altered by diffraction effects, not by a "consciousness" of what any of the other photons are doing.

 

[owl37400]

.... in the meantime I've done a bit of reading on the single-electron scenario you mention.

I still don't see how this demonstrates a "consciousness" of what a preceding electron has done?

The probability of it landing on a "white band" area of the screen is greater than it landing on a "black band" area.

How does this suggest that it is somehow aware of what any other electron has done?

 

[oedipus]

Perhaps either you or oedipus could explain more clearly exactly why you think the young's slits experiment is relevant to a discussion about directional cables.

I know it is not relevant.

I was merely chastizing BBV for playing the "trust me I'm a Doctor" card, while failing to recognise the experiment that ben556473 was refering to.

BBV, let's see if you can put your qualifications to good use, by explaining why the experiment Ben was refering to isn't relevant to the question at hand (directional cables).

So far, you've dismissed the wrong experiment, brought up irrelevant concepts (lorentz, quantum entanglement) and said the "power is irrelevant" (hilarious) and told him "to go read a book". Tactics employed by "snake oil salesmen".

 

[ben556473]

Hello, the reason I posted this (the original post about the experiment) was in direct response to your post saying "Indeed. Surely the only way the cable could be affected by its direction would be if it somehow knew that one end was connected to an amp and the other to a speaker" .

 

[ben556473]

I think it brings into question 'cause and effect' If we use scientific thinking then we would assume that the reason something happens is because something else caused it to happen. In this experiment it is, apparently, impossible for this to be the case. If you throw a tennis ball in the air it will land somewhere, if, a little while later you throw another ball, it will also land somewhere. What this experiment suggests is that the ball you threw first is somehow determining where the second ball will land even though its just lying on the floor somewhere and has nothing to do with your arm or the second ball

 

[ben556473]

Anyhow I hope this helps a little, I will try and refrain from discussing this further as it is an abstract topic in relation to this forum. But very good fun to chat about!

 

[owl37400]

Hello, the reason I posted this (the original post about the experiment) was in direct response to your post saying "Indeed. Surely the only way the cable could be affected by its direction would be if it somehow knew that one end was connected to an amp and the other to a speaker" .

Sure, that's fair enough.

I'll admit it was a rather vague remark to make because I don't quite know what I mean by the cable "knowing" what end is connected to what.

I suppose what I was getting at was that the cable would have to somehow change in its nature along its length, in order for turning it around to affect the system in any way, given that we have agreed that the current is not flowing in one direction.

So it would have to be thicker at one end than the other, or painted pink at one end and green at the other, or something like that, before turning it around could change anything in any way.

And I would have thought that the definition of a cable is a conductor with uniform properties along its length.

Even if you might say that the electrons in the cable "know" which end the amp is at, then I would have thought they would soon realise once you'd turned the cable around, and alter their behaviour accordingly.

 

[owl37400]

I think it brings into question 'cause and effect' If we use scientific thinking then we would assume that the reason something happens is because something else caused it to happen. In this experiment it is, apparently, impossible for this to be the case. If you throw a tennis ball in the air it will land somewhere, if, a little while later you throw another ball, it will also land somewhere. What this experiment suggests is that the ball you threw first is somehow determining where the second ball will land even though its just lying on the floor somewhere and has nothing to do with your arm or the second ball

My interpretation is that the experiment merely suggests that the second "ball" will have a higher probability of landing in a certain area than in another area. I don't see how it sugggests the location of the second landing is affected by the first.

 

[Paul Ranson]

What this experiment suggests is that the ball you threw first is somehow determining where the second ball will land even though its just lying on the floor somewhere and has nothing to do with your arm or the second ball

The experiment doesn't show this at all.

Paul

 

[Paul Ranson]

and said the "power is irrelevant" (hilarious)

Surely the whole point of the experiment with very low powers is to show that the power in the Young's Slits experiment is irrelevant. We only expect it to be relevant because of our poor analogies.

Free your mind etc.

Paul

 

[ben556473]

If I read you correctly, the reason a very low powered light source is used is to provide a gap (gap of time, any length produces the same effect) between each particle passing through the slits so as to render any actual interaction between them impossible. The word probablilty is often used when it need not be. My recollection (which could be wrong) was that no particles went to the wrong part of the diffraction pattern at all. That its construction was totally ordered.

 

[Tenson]

Why should something in the past not affect something that happens in the future? I do it all the time...

Can't photons exist in two places at the same time anyway? Or is that electrons... Something can! :MILD:

 

[ben556473]

I agree, but we would want to explain how it could effect this change. If the two events appear to be independant of each other by what mechanism can it cause the change? (nobody knows by the way). As far as things existing in two places at once I think I dont know. Logically one thing cannot be in two different places at the same time, but if time is not changing for you (as a photon) then you could be everywhere at the same time! I wrote a paper on time and what causes it to pass in a certain direction for A level physics 'Entropy and the Arrow of time'. I think if you can understand that it is the overall increase in disorder(entropy) throughout the universe that causes time to pass as it does then you are a good way to understanding mans take on everything. This is based on thermal physics and is what I would call real physics and can be understood logically. The conclusion is arrived at by 'sound science'. I must go to bed now sorry for rambling.

 

[Tenson]

As some bloke once said 'Disorder increases with time because we measure time in the direction in which disorder increases.'

 

[anon_bb]

Ben, the lack of understanding is yours - I did not say you referred to a different experiment I said you referred to an entirely unrelated concept in your explanation namely quantum entanglement which is nothing to do with youngs fringes at all. In fact what you have described is never discussed amongst physicists as it is a) entirely incorrect physics and b) mystical hogwash which has no relation to the physical concepts it is being linked with in order to make a vain attempt of providing said hogwash with some kind of authority. Using your arguments to claim a cable "knows" which end is connected to where is patently ridiculous. Your "cause and effect" post is probably the most risable thing I have ever read in a hifi forum. Even with a low powered light billions of billions of photons are passing through the slits at the same moment.

Oedipus - you are incorrect, I did recognise the experiment - that wasnt the part I was challenging. In science the onus is on the person propounding the theory to show the relevence - why should youngs fringes have anything to do with cable directionaility? No reason at all. And Ben brought up the topic of entanglement. No - snake oil salesman spout pseudo science. Mine was correct science. If you can proove otherwise please do so. Power is irrelvent to the youngs fringe pattern - if you think that is hilarious you obviously need a refresher o-level physics course - if you ever did it in the first place. I charge £25 per hour and I advise you to take me up on that offer.

Firstly the reason I wrote 'no comment' to brizonbiovizier was because what he wrote showed his lack of understanding ( he was telling me that I was talking about a different experiment, which is an obsurd way to argue.) This was kindly highlighted by Oedipus. What I said is not mysticism, it is a common discussion among physicists.

 

[anon_bb]

Thats entropy tenson

Ben just because everything has cause and effect does not mean everything is casually related. In addition some things are random or chaotic. It seems you dont really understand probability either.

Things can be in two places at once - or even a distribution of places - at the quantum level before observation causes the probability wave function to collapse. Even then certainty of measurements has planck limits. Entropy does not cause time to pass - except in human perception due to the chemical nature of our brain processes. The general relativisitic equations for the universe contain no entropy component in the discription of time. Extending it to mans take on everything is very weak philosopy. Its coffee table mish mashing of half baked interpretations of physics for daily mail readers.