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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

#211

Post by kgwgk »

bsder wrote: post #165
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.

> Slow down. Assuming that time moves in one direction is not comparable to geocentrism. Why not? The "arrow of time" almost always requires thermodynamic arguments. And that requires a concentration of "low entropy" to move toward "high entropy". Which, by definition, are "boundary conditions" and not a fundamental part of your physical rules. If, for example, your universe is entropically uniform, is there an "arro…

> If, for example, your universe is entropically uniform, is there an "arrow of time"? And, even if there were, could you detect it?

What does that even mean? If your universe is entropically uniform there is no “you”.

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

#212

Post by mellosouls »

psychphysic wrote: post #181
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…

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.

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

No. At least as early as Arthur Eddington when Penrose was a twinkle in his dad's eye.

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

#213

Post by yeahwhatever10 »

psychphysic wrote: post #181
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…

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.

Explaining an idea is not equivalent to taking credit for it.

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

#214

Post by CuriouslyC »

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.

Geocentrism seemed reasonable until it didn't.

If time is a true dimension rather than just something we model as a dimension, it's not unreasonable to think that outcomes in the present could be influenced by constraints that exist in the future - if the "universe" function must be valid according to some constraints at all points in the time dimension, "past" states that lead to invalid future states will never occur.

The idea of invalid universe states is of course purely fun conjecture, but this same concept also maps to probable vs improbable universe states as well. If a future state is improbable (in the sense of a Bayesian prior according to some underlying distribution of energy in the universe) that might cause the universe to evolve in a way that seems improbable at the moment by moment level, but is actually the most probable sequence of events when integrated over the entire duration of the universe.

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

#215

Post by psychphysic »

yeahwhatever10 wrote: post #213
psychphysic wrote: post #181

Earlier quoted context omitted.

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.

Explaining an idea is not equivalent to taking credit for it.

> Carroll's argument

This assigns credit to Carroll.

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

#216

Post by willis936 »

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.

Time could move backwards if we lived in a time symmetric universe. We don't. Maybe if you flipped the charge and handedness of the entire universe you could also reverse time, but that's yet to be tested.

https://youtu.be/L2idut9tkeQ

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

#217

Post by Jcowell »

psychphysic wrote: post #215
yeahwhatever10 wrote: post #213

Earlier quoted context omitted.

Explaining an idea is not equivalent to taking credit for it.

> Carroll's argument This assigns credit to Carroll.

It merely says that Carrol argued. The idea within the argument was no means assigned to her but used to make/support it.

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

#218

Post by beiller »

resource0x wrote: post #169
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.

If the direction of time is reversed, the eggs become whole again, but your memory of them once being scrambled is reversed, too, so you don't notice anything unusual. (It's like a rollback of database transaction, where not only the database state, but also the state of everything, including your brain, is getting rolled back)

If the future could affect the past, it suggest that then if time reversed, you would notice something unusual right? Kind of like suggesting there is a side effect in your function (consciousness). Kind of like how today, past events can influence the future like we act differently from learning from mistakes.

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

#219

Post by dasil003 »

VeninVidiaVicii wrote: post #170
brwck wrote: post #155

Earlier quoted context omitted.

It's not just a matter of our subjective experience of time, it's a matter of the laws of thermodynamics and entropy. Time moves in one direction is another way of saying entropy always increases. If time could move in the opposite direction, then entropy decreases which breaks our understanding of physics.

It's really interesting to think about how we struggle to express the idea of the future having a causal impact on the past. I reckon this is because our language and our understanding of time are limited. Our brains like to process events in a linear sequence, from past to present to future, but this view of time might not fully capture how everything in the universe is interconnected. It's possible that our languag…

Right. "Time only moves in one direction" is not saying much more than "our consciousness experience time moving in one direction". The very idea that time "moves" is entirely related to our vantage point. If our perception were not bound to time, then the nature of cause and effect might look completely different.

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

#220

Post by CuriouslyC »

stkdump wrote: post #200

If time were symmetric, wouldn't that mean instead of causality (future is influenced by the past) and retrocausality (past is influenced by the future), there is no preference and in effect no causality at all? A&B are necessarily connected, but none of them is the cause of the other.

If you think of it as a series of states with some prior probability, and jumps from state to state also have some probability, it isn't so much causal as correlated.

If time is a true dimension and reality is the most probable universe when integrated over all of time, improbable states and transitions might occur in the "past" in order to enable high probability states and transitions in the future.

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