Saturday, 14 June 2008

Tangled Up In Quanta

After that last post I got all depressed and went looking for some funky science stories to cheer myself up.

And I found one.

Quantum entanglement is a truly bizarre phenomenon, even by the way-out-there standards of quantum physics.

The idea is that if two photons of light become "entangled" at a quantum level, then the state of one will instantaneously affect the state of the other, even if they are separated by thousands or maybe even millions or billions of miles.

The potential applications of this, from faster-than-light communication to quantum cryptography, are staggering.

The state of each photon is not set until observed (in line with Heisenberg's uncertainty principle, or if you prefer, Schrödinger's cat), so observing one photon affects the state of the other.

All lab experiements to date have supported the theory of entanglement, but having both photons Earthbound introduces a potential loophole, whereby the observation might have been in advance, and therefore the effect not truly instantaneous.

The solution? Send one of the entangled photons to the International Space Station and leave the other one on Earth.

Due to the relativistic movement between the two photons, an observer on Earth and an observer on the ISS could both claim to have measured their photon first.

That's truly exciting. Nobody knows how this will turn out.

Now if only we could get some funding for further study of boredons.

10 comments:

David said...

I have been reading the comments about relion etc for some time now and have for a while intended to enter the debate. Even though I am a Christian, I have to admit that many of the comments about religion are sadly all too true.

However I do not agree that all religion can be rejected because some adherants do not live up to what they should, or are just downright evil. Consider the fact that some scientists misuse their position (I do not just mean by assisting in making arms etc that are used to inflict destruction on people). Some scientists fake results and otherwise violate accepted scientific norms. Does this mean that we should reject all science because some scientists fall short??

Quantum Physics is indeed weird science to some, mainly because it deals with concepts that we usually find difficult to understand.

I have a very interesting book by a Quantum Physicist who postulates that by using Quantum Phsics the six days of creation (as apparently stated in the Bible)can be reconciled with the millions of years apparently shown in the geological record.

The basis of his argument is that time moves at different rates under different conditions (as per Einstein). It therefore depends on which side of the Big Bang you are looking from. As a Christian I find this a very interesting theory. Unfortuneately there is currently no way that I know of that it can be proved (or dis-proved)

The problem with both religion and science is often that we try to put things into neat little boxes, usually based on pre conceived ideas (or what we wish was so)instead of admitting that we cannot be sure of many things.

Matt said...

That's fair enough.

I should say, though, that most atheists don't reject religion because of the behaviour of its adherents. That's just a cheap and easy way to attack religion (and I know I've been guilty of this in the past).

Their rejection of religion is actually the rejection of religious thinking.

It's rejected for exactly the same reason that you might reject belief in astrology or water divining or the healing power of crystals.

It's all just claims without evidence.

That it does good in some people's lives is unquestioned. All these other things do too. But that doesn't make it true.

David said...

An interesting question follows from the rejection of religion as being not true because there is no scientific evidence to show that it is true. It would seem to be more accurate to say that there is, as yet, no known scientific evidence to say that religion is true.

I readily admit that some claims by some religious people can be scientifically shown to be false, but this seems to be quite different to saying that all religion is false because we do not currently have the scientific evidence to prove it true. Who can say what may (or may not) be found in the future?

If the only truths are those that we have current scientific evidence to demonstrate, then how could we ever make new scientific discoveries? There would be no truths that we do not already know. Obviously this is not the case. Therefore to say that religion is not true because we cannot (at present) prove it scientifically seems to be an unprovable assumption, hardly a scientific approach.

All that can be said is that at this time we cannot prove, or disprove, religion using current scientific means.

As I understand the scientific method a theory is postulated and proved true by supporting evidence. Lack of supporting evidence leaves a theory not proved which is different to being proved incorrect. A theory can only be proved incorrect if evidence is produced to prove a mutually exclusive case to be true.

Matt said...

You're absolutely right . . . religious claims may be proven at some point in the future.

For example if, as many Christians believe, Christ physically and spectacularly returns to Earth then that'll be pretty conclusive proof.

But the point is that today, as of right now, there is no evidence. Yet despite this, these claims are still believed unquestioningly by millions.

That's the kind of thinking, religious thinking . . . unquestioning willingness to believe without evidence, that I and other atheists reject.

David said...

Matt, following on from the view that scientists only believe that for which they have evidence, what do you think of the idea that being a scientist and being an atheist are mutually exclusive states?

Consider the following definitions from the Collins Australian Dictionary.

atheism: (Gk a- without + theos god) the belief that there is no God.
Meaning that an atheist is one who believes that there is no God.

As I have argued previously not having evidence to support a theory is quite different from having evidence that disproves that theory by proving a contrary case. As far as I am aware science says that there is no evidence to support the idea of God, but does not have definitive evidence to prove that there is no God.

Give the above it would seem that a scientist may be an agnostic (Gk a- not + gignoskien know) a person who believes that one cannot know whether there is a God, or anything beyond material phenomena, because science claims that there is no evidence to either prove or disprove God.

To be both a scientist and an atheist seems to require evidence that there is no God, not just lack of evidence that there is a God. What do you think?

Matt said...

Interesting point. Although I must disagree that the atheist is required to produce evidence that there is no God.

The significant claim that there is an omnimpotent and omnipresent God surely puts the the burden of proof on the believer.

Bertrand Russell offered the lovely example of a teacup orbiting Jupiter. We're all quite comfortable not believing in that teacup without necessarily having to provide explicit proof.

To the atheist, not believing in God is exactly the same.

David said...

I remember hearing the Jupitor example from a Philosophy Lecturer in my Dip Ed. although I think he used the example of a silver tea pot.

I see your difficulty. Sorry, but I still say that if scientists only believe what can be proven, not what is comfortable, that being a scientist and an atheist are mutually exclusive positions.

Many people believe their religion for no other reason than it is comfortable.

Surely if a scientist takes a position they have to be able to prove their thesis if they are to follow the scientific method.

PS I find this a very interesting discussion.

Matt said...

I don't think it's correct to say that scientists will only believe what can be proven.
After all, lots of scientists believe in God.

A scientist, just like anyone else, can believe all sorts of things without evidence.
But a scientist will (or should) only promote as fact things that can be proven.

The point is that science is only concerned with examining and interpreting what can be observed and measured.
In that sense, the existence or non-existence of God is simply not a scientific question.
It can't be, because there's no objective evidence to examine or measure or test.

From there, the argument can go two ways, neither of them scientific because now we're outside the realms of science.
The first is to say that there are intangible reasons to believe (faith, comfort, a sense of belonging).
The second is to say that no particular evidence means no particular reason to subscribe to any particular faith.

Which way you go is a purely personal choice.

P.S. me too.

David said...

An interesting question arises from the above discussion, namely, Is the only truth scientific truth???

Is there truth which cannot be proved by traditional scientific means???

You seem to be saying in the previous posting that things which cannot be proved by science are just a matter of opinion although scientists may believe such things. If this is so are scientists who have such beliefs acting in a scientific manner???

What about relationships such as love between a couple, or parents and children, or a person who will voluntarily sacrifice themselves to save someone else???

How can these be explained by science. If they cannot be thus explained do they really exist??

Matt said...

Love and poetry and beauty are things not necessarily explainable by science.

So yes, of course there are things that are outside the realms of scientific investigation.

To say that they are not subject to scientific analysis is not to say that they don't exist, or even that they're not worthwhile. They clearly do and they clearly are.

It's just a question of relevance. Science is only concerned with things that can be objectively known. It has nothing to say about anything else.

A scientist doesn't have to look at everything scientifically, any more than a piano player has to look at everything in terms of musical scales.