Do I Misunderstand The Double Slit Experiment

[David Sklansky]

If we take your stance to its extreme one could say that seeing a man crucified and than coming back to life is simply an observation that, though mysterious, is just the way nature works. Same with observing that people who wear yamulkes get their prayers answered.

As for the double slit experiment, it is my understanding that one of the explanations proposed seriously by physicists is that every time a measurement is made the whole universe breaks in two. Or something like that. Are you OK with that but not OK with the explanation that there was some sort of intelligent design regarding quantum theory?

[DougShrapnel]

David, perhaps another explaination might help with regard to the double slit experiement. Light travels as a wave from point a to point b. Even thru slits. When you locate the light you create a new point. So the light now travels as a wave from point a to the new point near a slit, and then continues on it's way to the point b as a wave. There is no wave of light at the slits, hence the interference pattern disappears when we observe light with slit information. A major problem in the 40 year old books was that things couldn't be both a wave and a particle. It's now thought by many that everything is on a wave-particle duality, very similar to how location and speed are complementary.

[madnak]

[ QUOTE ]
As for the double slit experiment, it is my understanding that one of the explanations proposed seriously by physicists is that every time a measurement is made the whole universe breaks in two. Or something like that.

[/ QUOTE ]

Yes, but that's incomplete. Measurement per se is irrelevant. According to the Many Worlds interpretation, every time particles interact the universe splits. Measuring particles necessitates interacting with them, so measurement does "split the universe," but most of the "universe splits" are unrelated to measurement (and certainly unrelated to consciousness). This hardly implies any intelligent design - certainly no more than anything else does. What it implies is that the universe is a complex sort of thing that isn't ripe for analogy. It's not a "big dark room" like most people seem to intuitively think.

Measurement is a big deal because everything we know about the universe comes from our measurements. Not because measurement appears to have some special properties.

Also, keep in mind that physicists as a group are particularly likely to be atheists. That is, the people who do understand the double-slit experiment are likely to disbelieve in intelligent design. This wouldn't make much sense if the DSE implies ID.

[luckyme]

[ QUOTE ]
As for the double slit experiment, it is my understanding that one of the explanations proposed seriously by physicists is that every time a measurement is made the whole universe breaks in two. Or something like that. Are you OK with that but not OK with the explanation that there was some sort of intelligent design regarding quantum theory?

[/ QUOTE ]

I'm ok with any conjecture, even theistic ones. I just don't take it as useful until something testable comes out of it with measurable predictions, etc.

If the universe splits in two at each option, so be it. What am I supposed to do, start spraying everything with Crazee Glue?

ID isn't an explanation in the same class. It's essentially a non-explanation, an explanatory dead-end. Even if it were true, there is no way to know when we reach that throwing-up-hands limit, track record is that some genius comes along and gives us a non-ID explanation.

[ QUOTE ]
If we take your stance to its extreme one could say that seeing a man crucified and than coming back to life is simply an observation that, though mysterious, is just the way nature works.

[/ QUOTE ]

Of course. If men are trapped under ice for an hour and come 'back to life' then that's the way our species performs. If we do it after crucifixion it'd be an interesting discovery and I can't think of a reason to say, " hey, we can't do that... it defies logic". So far, people crucified properly have done the right thing and stayed dead.
The universe doesn't run on logic, it does what it does and we try to understand it logically. It's not the same thing.

luckyme

[David Sklansky]

"Measuring particles necessitates interacting with them, so measurement does "split the universe," but most of the "universe splits" are unrelated to measurement (and certainly unrelated to consciousness). This hardly implies any intelligent design -"

I wasn't saying that at all. I was simply wondering luckyme would be so sceptical of an intelligent design theory but not of an equally crazy sounding many worlds theory.

[madnak]

[ QUOTE ]
David, perhaps another explaination might help with regard to the double slit experiement. Light travels as a wave from point a to point b. Even thru slits. When you locate the light you create a new point. So the light now travels as a wave from point a to the new point near a slit, and then continues on it's way to the point b as a wave. There is no wave of light at the slits, hence the interference pattern disappears when we observe light with slit information. A major problem in the 40 year old books was that things couldn't be both a wave and a particle. It's now thought by many that everything is on a wave-particle duality, very similar to how location and speed are complementary.

[/ QUOTE ]

I'm going to attempt a broad intuitive explanation. Someone let me know if I'm way off-base. I know I'll be off-base, I don't know that any intuitive explanation can be on-base, but I'm hoping to be "close enough." I'll use Muppet's up/down idea.

There was a time when scientists saw particles, and saw that they were either up or down. Scientists also saw waves, and believed that waves were different from particles.

Then some experiments showed strange things. Certain particles seemed to be both "up and down" at the same time. Some waves seemed to act like particles sometimes. None of this made much sense to the scientists.

But then they figured it out. There are waves. These waves have up and down properties. When one wave interacts with another wave in a certain way, the first wave turns into a particle - basically the whole wave is "pulled together" into the point at its leading edge. When the wave turns into a particle it starts behaving like one - like a little marble instead of a ripple across water.

Though the wave itself has up properties and down properties, when that wave turns into a particle it becomes either up or down, one or the other. It's completely random which way the particle will be. But it will always be either up or down, not both.

This randomness was interesting to scientists, and some possible explanations were raised. One of these explanations was the following - when a wave turns into a particle, it retains both its up properties and its down properties. In order to do this, the wave creates two universes. In one of these universes, it becomes an up particle, and in the other universe, it becomes a down particle. So whenever a wave becomes a particle, new universes are created.

WRT the double slit experiment, it's simple. Measuring a wave causes it to turn into a particle. If we let a wave move through two slits and then measure it, we see a wave. The wave will turn into a particle only after we measure it. But if we measure the wave before it goes through the slits, and then measure it again after it goes through the slits, we see a particle. The first time we measure the wave we see a wave, but then it turns into a particle, so the second time we measure we see a particle. This was confusing to scientists at first, when they thought that waves and particles were separate.

Using this explanation David, it should be easy to see why 1, 2, and 3 in your OP do happen, and 4 does not happen.

[madnak]

[ QUOTE ]
"Measuring particles necessitates interacting with them, so measurement does "split the universe," but most of the "universe splits" are unrelated to measurement (and certainly unrelated to consciousness). This hardly implies any intelligent design -"

I wasn't saying that at all. I was simply wondering luckyme would be so sceptical of an intelligent design theory but not of an equally crazy sounding many worlds theory.

[/ QUOTE ]

Ah. I see. Well, I think they're similar. Both have no real evidence going for them, and both introduce unnecessary complexities. But I guess some math is starting to be consistent with the MWI, so it's getting more popular.

[Schweitzer]

[ QUOTE ]
I run the double-slit experiment but do not observe the slit the electrons travel through. Someone a light-minute away with a powerful telescope flips a coin to decide whether to observe them. Will I see an interference pattern or not?

If I see an interference pattern then the observer should be able to see which slit each electron went through and find a contradiction.

If I do not see interference then I know that the observer will not observe the experiment one minute from now and in effect know the future result of his coin toss. I have observed an effect before the cause.

[/ QUOTE ]

Maybe I am slow but I still do not understand what will happen here. I can't see an interference pattern because the observer would be able to look at the experiment a minute later and see which slit the electrons went through. (Which would be both if there is an interference pattern)

If I see a particle-type pattern, then that would seem to indicate that the light forced a wave collapse whether or not the light was observed. I was taught that this will not happen if the light is not observed.

The only other possibility I can think of is that the observation one minute in the future caused a collapse, which seems impossible.

[luckyme]

[ QUOTE ]
I was simply wondering luckyme would be so sceptical of an intelligent design theory but not of an equally crazy sounding many worlds theory.

[/ QUOTE ]

One major problem with ID is it only applies just when it's not needed. The universe gets simpler and simpler as we drill down and the need to call in an ID'er virtually disappears.
When we couldn't figure out how blood flows or birds fly or why the plague killed us, that was the time we could call for a designer if we were so inclined ... when things were complex. Now that we understand things down to simple interactions at the quantum level, why would "some intelligence that explains this complexity" be needed ... the complexity only existed at the macro level.

luckyme

[David Sklansky]

What?