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

vice.com

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

#331

Post by brigandish »

yesenadam wrote: post #284
ChancyChance wrote: post #195

It's an article about QM. On Vice. About a QM thought experiment. On Vice. Why would there be any expectation of scientific rigor whatsoever? "retrocausality, may seem like science fiction grist at first glance" Stop there, vice.

The main thing I didn't like about it was pretending it's all scientists involved and not philosophers. The article talks mostly about Huw Price—and from phrases like "Scientists, including Price", you'd think he's a scientist. He's an Australian philosopher. He was my professor for a couple of philosophy-of-science-related courses at Sydney Uni 20 years ago. He started the Centre for Time there I believe. He's a gre…

It’s common amongst journalists, certainly of late.

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

#333

Post by [deleted] »

Rury wrote: post #329
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…

> 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 generate complex structures in defiance of the regular direction of entropy It doesn't defy the direction of entropy. Frankly, I'm not sure why you have that notion? Entropy is a measure of system's state of equilibrium. Moving energy from a concentrated source, and distributin…

[deleted]

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

#334

Post by coderenegade »

Rury wrote: post #329
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…

> 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 generate complex structures in defiance of the regular direction of entropy It doesn't defy the direction of entropy. Frankly, I'm not sure why you have that notion? Entropy is a measure of system's state of equilibrium. Moving energy from a concentrated source, and distributin…

Entropy only increases on average. You can decrease it locally, for example, making steel from iron ore. You generate heat, so you still get a net increase, but you could easily redefine your boundary to only include the local decrease in entropy (the steel from ore).

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

#335

Post by sbaiddn »

Nevermark wrote: post #72
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?

While most laws of physics may be time symmetric, the laws of thermodynamics are not - wherever there is a gradient in entropy. In very informal terms, anywhere where there is very low entropy (higher order), any direction away from that will likely (to the point of certainty) be in a direction of higher entropy (lower order). For instance, if you have a jar of red & blue marble, with high order (such as perfect alte…

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

Im not saying you're wrong, but then there's Poincare's recurrence theorem. Entropy is funky. (Certainly not practical amounts anyway)

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

#337

Post by zone411 »

TeMPOraL wrote: post #324
zone411 wrote: post #302

Earlier quoted context omitted.

"there is 10 million times more entropy in that radiation [cosmic microwave radiation] than there is in all of the mass of the universe" https://news.berkeley.edu/2016/09/20/new-book-links-flow-of-...

But then, this is just entropy from a one-off event long ago. Meanwhile, life is an entropy producing reaction with a strong exponential factor. To butcher an insightful quote by (IIRC) Hamming, any positive slope will eventually make up for y-intercept of a constant function.

It underlines the idea that the entropy-time connection is pretty shaky though.

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

#339

Post by omazurov »

>...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.

... or sideways!

If you want a visual model that may help to build some intuition about that, I have one at [1]. Retrocausality is not explicitly spelled out in that model but "it's uh... uh... it's down there somewhere".

[1] https://github.com/OlegMazurov/Janus

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

#340

Post by tim333 »

btilly wrote: post #322
memling wrote: post #311

Earlier quoted context omitted.

> Philosophers professing to be scientists has been troubling me more and more the past few years. Scientists professing not to be philosophers has been troubling me more and more the past few years.

Why does it bother you? As Richard Feynman said, "Philosophy of science is about as useful to scientists as ornithology is to birds." Sure, lots of what scientists do, including Feynman, involve an implied philosophy. It is easy to read https://calteches.library.caltech.edu/51/2/CargoCult.htm or https://history.nasa.gov/rogersrep/v2appf.htm and extract a lot of important philosophical ideas from them. But I have yet…

Feynman was actually quite sophisticated philosophically eg. “The test of all knowledge is experiment. Experiment is the sole judge of scientific truth.” I think when there is a purpose to philosophy eg. understanding science, it works better. When there isn't really philosophers tend to in many cases just discuss what other philosophers have said about each other which tends to get a bit circular and pointless.
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