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I'm answering questions from the 'hardest exam in the world'

blog.nabeelqu.com

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Re: I'm answering questions from the 'hardest exam in the world'

#11

Post by esrauch »

mcarvin wrote: post #10
nqureshi wrote: post #8

Earlier quoted context omitted.

Saying p=0.5 necessarily implies the 1/2 thing. Neither implies any stance on whether it's subjective/objective so far. The 'objective' conclusion there requires the further fact of mind-independence, which is based on 'you can't change the odds that a fair coin comes up heads just by thinking about it' type arguments. So it's not circular/question-begging, IMO.

When a fair coin is tossed it will either come up heads or it wont. Put another way, the probability of getting heads is 1 or 0, unless you believe that something magical happens to the coin while it is in mid-air that somehow makes it impossible to predict what will happen when it lands (given a complete set of data). So the outcome of the coin-toss is knowable, it just happens to be complex enough that it is not kn…

Quantum mechanics?

Re: I'm answering questions from the 'hardest exam in the world'

#12

Post by JumpCrisscross »

mcarvin wrote: post #10
nqureshi wrote: post #8

Earlier quoted context omitted.

Saying p=0.5 necessarily implies the 1/2 thing. Neither implies any stance on whether it's subjective/objective so far. The 'objective' conclusion there requires the further fact of mind-independence, which is based on 'you can't change the odds that a fair coin comes up heads just by thinking about it' type arguments. So it's not circular/question-begging, IMO.

When a fair coin is tossed it will either come up heads or it wont. Put another way, the probability of getting heads is 1 or 0, unless you believe that something magical happens to the coin while it is in mid-air that somehow makes it impossible to predict what will happen when it lands (given a complete set of data). So the outcome of the coin-toss is knowable, it just happens to be complex enough that it is not kn…

Heisenberg uncertainty principle and the entire field of quantum mechanics?

Re: I'm answering questions from the 'hardest exam in the world'

#14

Post by mcarvin »

alphaBetaGamma wrote: post #9
mcarvin wrote: post #6

I understand the question quite differently. The question of objective probabilities is a question of whether the world is deterministic. If you believe the world is governed by physical laws and you further believe you understand those laws (physics), you consequently must believe that with sufficient information about the past you can predict the future (determinism). So if I was to throw a dart at a dartboard, wit…

Your premises are wrong: you can believe in physics, but the laws of physics could not deterministic. To the best of our knowledge this is the case[1], and we have strong indications [2] that this is a fundamental feature of nature: the non deterministic aspects do not come from our lack of understanding and knowledge. [1] http://en.wikipedia.org/wiki/Quantum_mechanics [2] http://en.wikipedia.org/wiki/EPR_paradox

Certain irony about saying that a LAW of physics is not deterministic. Conceded though that determinism does not hold up at the quantum level.

Disagree though that quantum non-determinism translates to non-determinism at the scale we experience [1]. Have never seen a Feynman diagram for a soccer ball. Which is why I feel comfortable saying that if you believe the macro world is deterministic then you cannot also believe there are objective probabilities (unless, as you indicated you are talking about the subatomic world).

Re: I'm answering questions from the 'hardest exam in the world'

#15

Post by mcarvin »

JumpCrisscross wrote: post #12
mcarvin wrote: post #10

Earlier quoted context omitted.

When a fair coin is tossed it will either come up heads or it wont. Put another way, the probability of getting heads is 1 or 0, unless you believe that something magical happens to the coin while it is in mid-air that somehow makes it impossible to predict what will happen when it lands (given a complete set of data). So the outcome of the coin-toss is knowable, it just happens to be complex enough that it is not kn…

Heisenberg uncertainty principle and the entire field of quantum mechanics?

Well played and conceded. So do we need two sets of rules? One for 'our world' and one for the subatomic world?

Re: I'm answering questions from the 'hardest exam in the world'

#16

Post by kstenerud »

Intuition 1 is incorrect.

The probability of the marble being under the box during that period of time was 1 because its state never changed. It was merely your incomplete knowledge that encouraged you to (incorrectly) assign a probability of 0.5. You've become confused over WHAT is the subject of your test.

If, however, you were to change the experiment such that there were two boxes, one with a marble and one without, you now have the ability to engage in real probability. The probability that a marble is present under each box is either 1 or 0. However, the probability that you will CHOOSE TO LIFT the box containing the marble is 0.5. This is not a probability of presence or absence of a marble; it's the probability that YOU will choose to look under a particular box.

Probability requires the possibility of change, and the probability of change in a marble's presence under a box (such as by teleporting from one box to another) is small indeed.

Re: I'm answering questions from the 'hardest exam in the world'

#17

Post by eru »

mcarvin wrote: post #14
alphaBetaGamma wrote: post #9

Earlier quoted context omitted.

Your premises are wrong: you can believe in physics, but the laws of physics could not deterministic. To the best of our knowledge this is the case[1], and we have strong indications [2] that this is a fundamental feature of nature: the non deterministic aspects do not come from our lack of understanding and knowledge. [1] http://en.wikipedia.org/wiki/Quantum_mechanics [2] http://en.wikipedia.org/wiki/EPR_paradox

Certain irony about saying that a LAW of physics is not deterministic. Conceded though that determinism does not hold up at the quantum level. Disagree though that quantum non-determinism translates to non-determinism at the scale we experience [1]. Have never seen a Feynman diagram for a soccer ball. Which is why I feel comfortable saying that if you believe the macro world is deterministic then you cannot also beli…

Determinism does hold up at the quantum level. Quantum mechanics is completely deterministic. Collapsing the wave function to a classic state, is the probabilistic aspect, if any.

Re: I'm answering questions from the 'hardest exam in the world'

#18

Post by ackien »

>To sum up: probabilities are (a) true or false, (b) regardless of what I believe about this probabilities. Estimated probabilities (c) depend on the prior knowledge of the mind in question. Moreover, (d) the fact that the probability is X is a fact about my mind.

I'm not sure why you then go on to say that probability is neither objective nor subjective, and that probability has traits of both (which seems somewhat like a contradiction), rather than conclude that there are two different kinds of probability: objective probability and subjective probability ('probabilities' and 'Estimated probabilities' as you even differentiate yourself). (And then there is the other interpretation of the question of whether objective probability even exists at all or wether the world is deterministic.)

Re: I'm answering questions from the 'hardest exam in the world'

#19

Post by nhebb »

nqureshi wrote: post #3
habitatforus wrote: post #2

Upvote, because I didn't know the 'hardes exam in the world' existed, and I now think it's awesome. Good luck.

Thanks. Did you check out the link to the general paper? One of my favourite questions from there: "Does the moral character of an orgy change when the participants are wearing Nazi uniforms?"

Q: Does the moral character of an orgy change when the participants are wearing Nazi uniforms?

A: Yes

Did I pass the exam?

Re: I'm answering questions from the 'hardest exam in the world'

#20

Post by pron »

eru wrote: post #17
mcarvin wrote: post #14

Earlier quoted context omitted.

Certain irony about saying that a LAW of physics is not deterministic. Conceded though that determinism does not hold up at the quantum level. Disagree though that quantum non-determinism translates to non-determinism at the scale we experience [1]. Have never seen a Feynman diagram for a soccer ball. Which is why I feel comfortable saying that if you believe the macro world is deterministic then you cannot also beli…

Determinism does hold up at the quantum level. Quantum mechanics is completely deterministic. Collapsing the wave function to a classic state, is the probabilistic aspect, if any.

I think that quantom mechanics makes us think differently about probability and determinism by giving the mathematical (human created) concept of probability a physical meaning. Similar to the example in intuition 2, a coin toss could be considered determinstic even if we do not try to predict the result. It is pre-determined that given a large enough number of coin tosses, very close to 50% of them would come out heads. Qunatom mechanics makes us consider probability as a physical property inherent in all physical objects. This way of thinking helps reasoning about genetic predisposition as well (which is always probabilistic). Just like any coin is "free" to make a choice, and yet it is certain that they would (almost) precisely split down the middle, so too can genetic predisposition can be said to be both constraining and not constraining at all at the same time.
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