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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

#181

Post by psychphysic »

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 think Carroll can take credit for the idea of the arrow of time being emergent from a local entropy initial state.

Roger Penrose proposed that as far as I know, when Carroll was probably a high schooler.

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

#182

Post by PartiallyTyped »

a257 wrote: post #168
PartiallyTyped wrote: post #162

Earlier quoted context omitted.

Any point is infinitely improbable when sampling with infinite precision, only because this calculation is not computable. Even if the point probability is 0 or approaching zero very fast, some event occurs with probability 1. The probability that life would evolve on a blue planet that its anthropomorphic inhabitants will come to call Gaia or Earth, has as a star Sol, in this corner of the Milky Way, in this particu…

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.

I think I was misunderstood. My comment regarding infinite precision was mostly aiming to argue that any single point has probability zero but an event still occurs.

This was then used again when mentioning earth to argue that depending on the definition of "order" here:

> And no practical amount of shaking the jar will ever return the marbles to a high order state again.

It is entirely possible to reach a state of higher order if you don't require that individual marbles don't hold the same arrangement relative to adjacent marbles, meaning that any permutation of marbles with identical color is acceptable.

This happens because the event you are asking for is a very large subset.

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

#183

Post by photochemsyn »

theGnuMe wrote: post #61
wootland wrote: post #15

As a non-physicist I'm not sure I'm interpreting this correctly. Does this essentially mean that all states in time already exist and our consciousness is just traversing this 4D space in one direction on the time axis? If so, does that mean that the big bang could actually be the end of the universe and we're just experiencing time in "reverse" toward an initial starting state that we perceive as the future?

I like this concept. Is there any sci-fi based on this premise?

The 'Dirac Beep' in this short novella (1973):

https://en.wikipedia.org/wiki/The_Quincunx_of_Time

Also, the concept of causality itself is a kind of underlying theme in Hannu Rajaniemi's "The Causal Angel" (2014) (3rd of a series).

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

#184

Post by ashirviskas »

prerok wrote: post #177
photochemsyn wrote: post #164

Earlier quoted context omitted.

It's difficult to see how such a hypothesis could be tested either experimentally or observationally. Sounds more like metaphysics? Stars shine until they run out of fuel, and the age of a star - the status of its fuel, the buildup of fusion products - happens as time passes. Life on planets taps into the flow of sunlight from the star (and/or the flow of heat and chemical energy from the a hot planetary core) to gen…

Well, of course not :) Entropy as direction of time just means that the chaos on the whole increases. So, to create an ordered structure, like a cell organism, the by-product is more chaos around it.

To add, life just speeds up the chaos by orders of magnitude, it's a perfect entropy catalyst.

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

#185

Post by prerok »

photochemsyn wrote: post #164
0xBABAD00C wrote: post #134

Earlier quoted context omitted.

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…

It's difficult to see how such a hypothesis could be tested either experimentally or observationally. Sounds more like metaphysics? Stars shine until they run out of fuel, and the age of a star - the status of its fuel, the buildup of fusion products - happens as time passes. Life on planets taps into the flow of sunlight from the star (and/or the flow of heat and chemical energy from the a hot planetary core) to gen…

I think that the real question is whether the death of the universe by cool down will happen before the arrow of time is reversed. To me it seems more like it will just slow down and then finally stop.

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

#186

Post by dekhn »

kridsdale1 wrote: post #117
7thaccount wrote: post #105

Earlier quoted context omitted.

Yep. Someone else already pointed out the well known counterargument to symmetry below regarding thermodynamics. You typically don't see scrambled eggs become whole again. I think that's pretty hard evidence to overcome. Granted, I'm not a physicist and I'm sure any physicist working on this totally understands that. Just wanted to point it out.

Scrambled eggs can become whole again by being consumed by insects, who are then consumed by chickens, who then lay eggs. The biological processes enabling that sequence can be said to have negative entropy.

Negative entropy (also called negentropy) isn't really a well-defined concept. Instead, better to say that biological processes harvest free energy to maintain order in the face of increasing entropy.

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

#187

Post by why-el »

marcus_holmes wrote: post #37

Interesting because it messes with the school of thought that everything is determined already and we're just following a sequence of actions that arise from the starting conditions of the universe. If causality is broken then maybe we have free will?

My favorite sentence on free will comes from Chomsky (who I think was probably quoting someone else): "if we don't have free will, then why are you arguing the point?"

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

#188

Post by soperj »

a257 wrote: post #163
soperj wrote: post #154

Earlier quoted context omitted.

There can't be an infinite number of marbles in a finite amount of space.

The number of possible states asymptotically approaches infinity, so we can model it as such. You can get a more "accurate" model using more math (with measure theory), but the terms will coalesce such that they are negligible.

negligible isn't zero, and time at a universe scale may be longer.

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

#189

Post by Notatheist »

yyyk wrote: post #150
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.

The comparison is bad all around. Geocentrism actually had decent reasoning and was not a superstition. It's just we couldn't see the parallax with then-current instruments. As soon as instruments allowed, humanity changed rather quickly.

Time moving in one direction actually has decent reasoning and is not a superstition. It's just we can't detect time moving backwards with now-current instruments. As soon as instruments allow, humanity will change rather quickly.

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

#190

Post by dekhn »

dietrichepp wrote: post #20
wisty wrote: post #3

Human instincts only apply to the systems that they're "evolved" to handle (or the systems we can readily observe and learn from). Think about big systems. The moon is a ginormous rock that's so big it is visible from thousands of km away, but it just hangs in the sky because it's moving so fast it can cheat gravity, but we can barely even see it move. Or think about how a star can somehow explode because it starts r…

I used to work at camp. You didn’t need to tell kids about fire; they could figure it out. Don’t touch the fire. Flashlights were too complicated. It’s night, a kid turns on their flashlight, points it in their eyes, says “ow” and can’t see where they’re walking until their eyes readjust. Flashlights are beyond our instinctual understanding of how the world works.

it's funny you mention flashlights. NO matter how many times I tell people not to point their flashlight at people's eyes, it happens (by accident) over and over. It bothers me a lot because I am very good at getting my eyes dark-adapted and as soon as somebody flashes me, I lose about 10 minutes of dark vision.
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