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A growing number of scientists are convinced the future influences the past

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Re: A growing number of scientists are convinced the future influences the past

#421

Post by a257 »

lupire wrote: post #373
TechBro8615 wrote: post #193

Earlier quoted context omitted.

I'm neither a mathematician nor a physicist, so I'm not nearly informed enough to elaborate on the subject properly, but I would note that the axiom of choice is not proven, and while you can mathematically divide a continuum into infinitesimally small sets, you cannot do the same to physical matter. From my understanding, many of the contradictions between classical and quantum physics arise at this boundary between…

This whole thread hinges on your not giving credence to the word "practically" , as in "approximately". No countably infinity needed, and Continuum Hypothesis isn't relevant at all in any way, as it is aboit uncountable infinity. Until you explain what you are trying to say, you aren't saying anything meaningful. The one showing hubris here is you, tossing around technical terms don't admit you don't understand.

Indeed, the original claim treats mathematics as a modeling tool, not philosophy. Nevertheless, it is my belief that untestable hypotheses about True Reality (should it even exist) are not debatable without causing migraines of epic proportions. There's no physics without mathematics -- as physicists say, shut up and calculate.

Re: A growing number of scientists are convinced the future influences the past

#422

Post by a257 »

dekhn wrote: post #198
a257 wrote: post #168

Earlier quoted context omitted.

A probability of zero does not mean that the event is impossible. When we refer to probabilities we are talking about probability densities. Infinite precision is a useful modeling tool in the same way that approximations of pi are useful.

In a well defined system, a probabiltiy of zero by definition means an event is impossible.

> Zero probability does not mean an event cannot occur! It means the probability measure gives the event (a set of outcomes) a measure zero. [0]

[0] https://stats.stackexchange.com/a/273398

Re: A growing number of scientists are convinced the future influences the past

#423

Post by a257 »

lupire wrote: post #376
dekhn wrote: post #198

Earlier quoted context omitted.

In a well defined system, a probabiltiy of zero by definition means an event is impossible.

In physics, nothing can be measured exactly, so exact events are in fact impossible. Measurements are approximate, and thus have finite extent, and thus can have nonzero probability. This whole thread is silly, The 2nd law is about probabilities which are asymptotically 0, so small in practice that we could never do experiments to frequentist probability empirically, using "jars of marbles" with more than 100 marbles…

That is a great point. The laws of thermodynamics exist as a logical consequence to fundamental statistical principles. It is statistical mechanics that gives rise to entropy, not the other way around. (hence the beautifully elegant equation S = Kb*ln(Omega) where Omega is the number of microstates)

I realize that programmers are not always good scientists. Yet some claims are absurd in ways that I now believe this phenomenon necessitates rigorous study.

Re: A growing number of scientists are convinced the future influences the past

#424

Post by kwhitefoot »

coldtea wrote: post #232
kwhitefoot wrote: post #16

> In addition to potentially rescuing concepts like locality and realism, retrocausal models also open avenues of exploring a “time-symmetric” view of our universe, in which the laws of physics are the same regardless of whether time runs forward or backward. Usually the fundamental laws are regarded as time symmetric already. What does this mean: > Instead, retrocausal models suggest that there is a mechanism that a…

> Surely future states inevitably correlate with past states? He means to correlate through effects going the future -> past direction...

Yes, of course. But that is not how correlation is usually expressed. And it also doesn't explain what it means. It just sounds like philosophers doing some hand waving.

What can it mean to have an effect propagating into the past? Surely our usual definition of time is simply a series of events. If so then it always points in one direction for the entity sitting at the leading edge, the current event is always succeeded by the next event.

All I have to go on is the article, perhaps the source material makes more sense.

Re: A growing number of scientists are convinced the future influences the past

#427

Post by patrakov »

kwhitefoot wrote: post #16

> In addition to potentially rescuing concepts like locality and realism, retrocausal models also open avenues of exploring a “time-symmetric” view of our universe, in which the laws of physics are the same regardless of whether time runs forward or backward. Usually the fundamental laws are regarded as time symmetric already. What does this mean: > Instead, retrocausal models suggest that there is a mechanism that a…

> Usually the fundamental laws are regarded as time symmetric already.

Well, in addition to time reversal, you also have to mirror the universe and replace all particles with their anti-particles.

Re: A growing number of scientists are convinced the future influences the past

#428

Post by explaininjs »

yyyk wrote: post #417
fdsafsd34 wrote: post #416

Earlier quoted context omitted.

Mmm, not really unpredictable, it is easy for thought exercises to avoid the dirty real world, but in the real world, Large Language Models have recently proven that many quite difficult abstract probability exercises, when taken to the real world and applying training, can be succesfully solved well beyond our most wildly expectations of precision, speed and accuracy. So yes, the prediction of the decision to have a…

> the prediction of the decision to have a ham sandwich tomorrow, for any given person is now, by the state of the art of applied mathematics and information science, a relative doable - if not plain easy - feat. Sure, the LLM may be able to guess by reasoning (e.g. 'He always eats ham sandwiches for breakfast and he probably wouldn't break his routine'), the same way we could guess at another person's behaviour, but…

Y'all talking around the central point of the paper, btw. If this interests you, I suggest diving in.

Re: A growing number of scientists are convinced the future influences the past

#430

Post by Viliam1234 »

0xBABAD00C wrote: post #134
jonny_eh wrote: post #77

> It may seem eerie to our brains, which process events sequentially, but the history of science is also littered with examples of human biases leading to bad conclusions, such as the Earth-centric model of the solar system. Slow down. Assuming that time moves in one direction is not comparable to geocentrism.

Here's the analogy, per Sean Carroll [1]: - There seems to be a special direction "down", where things fall by default, because we live in the vicinity of an influential object in space, called Earth - There seems to be a special direction "forward in time", where things happen by default, because we live in the vicinity of an influential event in time, called Big Bang If we had stuck to the local Earth context and g…

I don't have a problem with "time" meaning "away from the local Big Bang". But that does not imply that future causes the past.

Just like noticing that "down" actually means "towards the center of the local planet" did not make water suddenly flow uphill.

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