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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

#151

Post by jskulski »

sidlls wrote: post #108
whatshisface wrote: post #85

Earlier quoted context omitted.

It is because in both cases, you can work out that you'll never make an observation that really proves it one way or the other, but you might come up with some laws of physics that are more conveniently expressed in one way than another. They're both ultimately questions about your coordinate system, and in fact it is easier to invert time than it is to work out how everything's supposed to function in a rotating+sun…

It isn't because we have the observations we have. It might be mathematically easy to invert time, but empirically it's not so simple. Mathematical symmetries and expressions are nice, but then the actual physical consequences and requirements (e.g., material, time, energy inputs) sort of force one's hand. Also, geocentrism is actually disproven by numerous observations, which in fact guided the mathematical formulat…

We may not be able to observed it, and maybe can’t. Just like time slowing down would be imperceptible to the person on the spaceship nearing light speed. It takes the mathematics

Or if I’m lucky enough to have the time to watch the moon move slowly, it feels natural to my senses to say it’s moving across the sky. The moon feels like it’s moving around me. But I can stretch my brain and imagine the reality.

Sometimes math arrives first. We have the new maths (or an problem in current math), and that points to some possibility. Because it’s not observable, ignoring our senses is a requirement to develop that in the model and measurements and experiments. Eventually we are able to observe it.

I’m not familiar with history of astronomy. Would it be the case where the observations that lead to heliocentric thought we nuanced and had to build on more obvious perceptions that things aren’t adding up? Was the wobble of Venus part of that?

And you’re right, old models are useful and remain relevant a lot! The model of time moving linearly will likely always be the most useful model for navigating our daily choices (if we have any at all!)

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

#153

Post by kelseyfrog »

imsaw wrote: post #74
jspank wrote: post #65

Earlier quoted context omitted.

Reminds me of the Tralfamadorians from Slaughterhouse-Five. They are able to see in four dimensions so humans appear as fetuses at one end of the four-dimensional person and dying at the other end. https://en.wikipedia.org/wiki/Tralfamadore#Slaughterhouse-Fi...

Interesting concept. I wonder if it's compared with spatial 3D space, then how large would the 4th dimension of time be if it were to fit the timeline of a human lifespan

A natural interpretation leads to time being very large and us moving very very fast through it.

It's convenient to model our movement through space-time as occurring at the speed of light. Thus, the faster we move in space, the slower we move in time all the while the length of our space-time velocity vector is invariably c. We can then imagine 1 second of time being interchangeable with 299,792,458m.

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

#154

Post by soperj »

a257 wrote: post #97
soperj wrote: post #90

Earlier quoted context omitted.

> And no practical amount of shaking the jar will ever return the marbles to a high order state again. This can't be true. Take the case where there's only 2 marbles, it's likely that at some point that shaking them will return them to the original state. For higher numbers of marbles the probability becomes lower and lower, but is never 0.

With enough marbles, the discrete distribution behaves like a continuous distribution. The point probability of a continuous distribution is infinitely improbable -- in other words it is 0. (0.00..0..1 = 0 just as 0.99 repeating equals 1)

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

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

#155

Post by brwck »

epgui wrote: post #102
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.

I disagree, I think the comparison is pretty reasonable. Your entire experience of the world is defined and limited by the fact that your brain "only processes information in one direction of time" (for lack of better wording). Your personal experience does not necessarily map correctly to the real world. The same is true for both examples.

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.

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

#156

Post by lordnacho »

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…

That all makes sense, but why does cause and effect seem to go one way with the entropy arrow?

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

#158

Post by a257 »

TechBro8615 wrote: post #135
a257 wrote: post #97

Earlier quoted context omitted.

With enough marbles, the discrete distribution behaves like a continuous distribution. The point probability of a continuous distribution is infinitely improbable -- in other words it is 0. (0.00..0..1 = 0 just as 0.99 repeating equals 1)

> infinitely improbable -- in other words it is 0 This sounds like a rather bold statement to make, as long as we're already speaking so metaphysically.

The statement is mathematically correct [0].

[0] https://stats.stackexchange.com/questions/142730/px-x-0-when...

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

#159

Post by polishdude20 »

mywittyname wrote: post #148
polishdude20 wrote: post #109

Earlier quoted context omitted.

That would also mean that when I don't see or hear other people, they don't "exist" as physical things that can be seen or heard until I encounter a situation in which they would be. It's the same as "If a tree falls in the forest and nobody is around to hear it, does it make a sound?" But then again, that information has to be stored somewhere right? Like, if a tree falls in the woods and nobody is around, sure you…

> But then again, that information has to be stored somewhere right? As a collection of probabilities stored as a wave. If a bank account has a 50% probability earning a penny every second, the bank doesn't need to store all of the intermediate values for every "clock tick", but instead calculate how much has accumulated since the last time someone checked the account and store that value with a timestamp.

Where is this wave stored though? And what is the wave made of? A wave of what?
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