Freethought & Rationalism Archive

Keenanvin · 11-07-2002, 03:38 PM

Firstly, let me apologize if this end up in the wrong forum..
Secondly, DETERMINISM - in theory it is possible, right? I mean, it does make sense that atomic ( or subatomic ) randomness may not actually be random at all. At a subatomic levels, using appropriate tools, scientists could, in theory, predict the movement of a singular atom- how it would bounce and where it would end up after x seconds or microseconds, right? Are there any downfalls to determinism ( besides the argument of free-will), and if so, could anyone help me out by attempting to refute or support my argument presented?
Thirdly - this is a bit off topic, but does anyone know the formula for calcuating Intensity vs Distance ( ie, distance from a campfire, source of sound, anything that graphs hyperbolically in the first quadrant)
I=(something)(1/d^2), and i'm missing the (something, and im not sure it even exists)

anyhow, thanks for the help! - Keenan
:::edit::: spelling <img src="graemlins/banghead.gif" border="0" alt="[Bang Head]" />

[ November 07, 2002: Message edited by: Keenanvin ]

tronvillain · 11-07-2002, 04:22 PM

Yes, in theory, determinism is possible. Is it actual? At the moment there appears to be some degree of randomness, making prediction a matter of probabilities rather than certainties.

[ November 07, 2002: Message edited by: tronvillain ]

DigitalDruid · 11-07-2002, 05:49 PM

Bruised by physics? OK, here's some first-aid for you.

I=(something)(1/d^2)

You are right. That's the general form of the Inverse-Square law.

For light and sound it is I=S/4*pi*d^2, where S is the source strength.

[ November 07, 2002: Message edited by: DigitalDruid ]

Chip · 11-07-2002, 06:14 PM

Using some parenthesies, is the following correct?

I=S/(4*pi*d^2)

Thanks, Chip

Shadowy Man · 11-08-2002, 06:38 AM

Actually, that's flux.

For light, it is Flux = Luminosity/(4*pi*r^2), where Luminosity is in units of energy per time.

Oxymoron · 11-08-2002, 06:44 AM

Determinism has two problems:

Firstly, attempts to show that quantum randomness is an illusion caused by there being so-called "hidden variables" have all failed. I think I am correct in saying that it has recently been established empirically that there can be no hidden explanation of quantum wierdness. In other words it truly is random. On the other hand, quantum systems aren't always random. Do a wave-type experiment on an electron, it always acts like a wave; do a particle-type experiment on the critter, it's a particle. 100% determinate, 101% wierd.

Secondly, many systems that obey deterministic rules can have seemingly random and indeterminate behaviour. Crudely put, because we cannot specify numbers (and therefore starting conditions of the system) to an infinite number of decimal places, for a few systems and given a long enough period of time, the behaviour may be indeterminable even in theory.
For example, computer simulations of the solar system cannot determine its stability over the next billion years. The N-body model used to describe it has "singular" terms that grow over time and wash over the other terms in the equations. Some mathematical jiggery-pokery can alleviate this to some extent, but not for an arbitrary epoch.

What all this says is that there are limits to what we know, in terms of quantitative (how much, where, how fast...) values, and qualitative values (stable, unstable, oscillatory...) properties.

[ November 08, 2002: Message edited by: Oxymoron ]

wdog · 11-08-2002, 06:46 AM

tron,

I thought that the experiments of bell showed that there were no hidden variables, that determinism is not possible.

beausoleil · 11-08-2002, 02:31 PM

No local hidden variables - non-local hidden variables still work I believe, but are hard to conceive of. Even the hiidden variables thing is a little controversial - try a search under "Bell's Theorem" and "Experiment"

[ November 08, 2002: Message edited by: beausoleil ]

wdog · 11-10-2002, 08:17 AM

when I get time beau, but until then could you just tell me what you mean by a nonlocal variable? Do you mean an average, or expectation value?

Friar Bellows · 11-10-2002, 11:16 PM

Quote:

Originally posted by wdog:
when I get time beau, but until then could you just tell me what you mean by a nonlocal variable? Do you mean an average, or expectation value?

No, I seem to recall that local "hidden variables" are those which are constrained by the speed of light limit, while non-local "hidden variables" aren't constrained by this limit (and would thus violate special relativity). An associated phrase is "spooky action at a distance", coined by Einstein, if my memory serves correct. I think the most successful of the non-local "hidden variables" theories is <a href="http://www.bohmian-mechanics.net" target="_blank">Bohmian Mechanics</a>, but there are still huge problems with it. So there's some more phrases for you to look up.

11-07-2002, 03:38 PM	#1
Keenanvin Junior Member Join Date: Oct 2001 Location: Ohio Posts: 19	Physics Help needed! Firstly, let me apologize if this end up in the wrong forum.. Secondly, DETERMINISM - in theory it is possible, right? I mean, it does make sense that atomic ( or subatomic ) randomness may not actually be random at all. At a subatomic levels, using appropriate tools, scientists could, in theory, predict the movement of a singular atom- how it would bounce and where it would end up after x seconds or microseconds, right? Are there any downfalls to determinism ( besides the argument of free-will), and if so, could anyone help me out by attempting to refute or support my argument presented? Thirdly - this is a bit off topic, but does anyone know the formula for calcuating Intensity vs Distance ( ie, distance from a campfire, source of sound, anything that graphs hyperbolically in the first quadrant) I=(something)(1/d^2), and i'm missing the (something, and im not sure it even exists) anyhow, thanks for the help! - Keenan :::edit::: spelling <img src="graemlins/banghead.gif" border="0" alt="[Bang Head]" /> [ November 07, 2002: Message edited by: Keenanvin ]</p>

11-07-2002, 04:22 PM	#2
tronvillain Veteran Member Join Date: Oct 2000 Location: Alberta, Canada Posts: 5,658	Yes, in theory, determinism is possible. Is it actual? At the moment there appears to be some degree of randomness, making prediction a matter of probabilities rather than certainties. [ November 07, 2002: Message edited by: tronvillain ]</p>

11-07-2002, 05:49 PM	#3
DigitalDruid Senior Member Join Date: Aug 2002 Location: Florida Posts: 712	Bruised by physics? OK, here's some first-aid for you. I=(something)(1/d^2) You are right. That's the general form of the Inverse-Square law. For light and sound it is I=S/4pid^2, where S is the source strength. [ November 07, 2002: Message edited by: DigitalDruid ]</p>

11-08-2002, 06:44 AM	#6
Oxymoron Veteran Member Join Date: Sep 2002 Location: http://10.0.0.2/ Posts: 6,623	Determinism has two problems: Firstly, attempts to show that quantum randomness is an illusion caused by there being so-called "hidden variables" have all failed. I think I am correct in saying that it has recently been established empirically that there can be no hidden explanation of quantum wierdness. In other words it truly is random. On the other hand, quantum systems aren't always random. Do a wave-type experiment on an electron, it always acts like a wave; do a particle-type experiment on the critter, it's a particle. 100% determinate, 101% wierd. Secondly, many systems that obey deterministic rules can have seemingly random and indeterminate behaviour. Crudely put, because we cannot specify numbers (and therefore starting conditions of the system) to an infinite number of decimal places, for a few systems and given a long enough period of time, the behaviour may be indeterminable even in theory. For example, computer simulations of the solar system cannot determine its stability over the next billion years. The N-body model used to describe it has "singular" terms that grow over time and wash over the other terms in the equations. Some mathematical jiggery-pokery can alleviate this to some extent, but not for an arbitrary epoch. What all this says is that there are limits to what we know, in terms of quantitative (how much, where, how fast...) values, and qualitative values (stable, unstable, oscillatory...) properties. [ November 08, 2002: Message edited by: Oxymoron ]</p>

11-08-2002, 02:31 PM	#8
beausoleil Senior Member Join Date: May 2002 Location: US and UK Posts: 846	No local hidden variables - non-local hidden variables still work I believe, but are hard to conceive of. Even the hiidden variables thing is a little controversial - try a search under "Bell's Theorem" and "Experiment" [ November 08, 2002: Message edited by: beausoleil ]</p>

11-07-2002, 06:14 PM	#4
Chip Banned Join Date: Sep 2002 Location: Earth Posts: 382	Using some parenthesies, is the following correct? I=S/(4pid^2) Thanks, Chip

11-08-2002, 06:38 AM	#5
Shadowy Man Veteran Member Join Date: Jun 2002 Location: A Shadowy Planet Posts: 7,585	Actually, that's flux. For light, it is Flux = Luminosity/(4pir^2), where Luminosity is in units of energy per time.

11-08-2002, 06:46 AM	#7
wdog Veteran Member Join Date: Dec 2001 Location: Ohio, USA Posts: 1,547	tron, I thought that the experiments of bell showed that there were no hidden variables, that determinism is not possible.

11-10-2002, 08:17 AM	#9
wdog Veteran Member Join Date: Dec 2001 Location: Ohio, USA Posts: 1,547	when I get time beau, but until then could you just tell me what you mean by a nonlocal variable? Do you mean an average, or expectation value?

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