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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

#91

Post by explaininjs »

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?

Scott Aaronson's "Ghost in the Quantum Turing Machine" tackled this question in a way I found enlightening. It's a bit of a dense read (I needed a plane trip to sit down and focus on it), but it presents a compelling case for the possible reversal of time arrows when it comes to the effects of quantum indeterminism on macro scale interactions. In short: what if humans, somehow, someway, have the ability to "influence" the resolution of unobserved universal start-state quantum noise in order to affect our "will" onto the universe? Furthermore, what experiments could be done to validate or invalidate aspects of this hypothesis?

https://arxiv.org/abs/1306.0159

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

#92

Post by karmakaze »

It does make explaining some things much easier, like the "Delayed-choice Quantum Eraser"[0] experiment.

Basically what's possible next is anything that can solve for conditions set by the past, and some from the future.

[0] https://en.wikipedia.org/wiki/Delayed-choice_quantum_eraser

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

#93

Post by gpuhacker »

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?

Surely reminds me of Harry Potter and the Prisoner of Azkaban, where Harry is saved by himself as he at some point in the future travels back in time to save himself.

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

#94

Post by quijoteuniv »

__MatrixMan__ wrote: post #84
quijoteuniv wrote: post #76

Earlier quoted context omitted.

You can wish yourself well in the past. I believe this works.

I think of personal growth as a conspiracy between present me, past me, and future me. Where our motives are aligned, good things happen.

This is good! And ask for help from the future :)

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

#96

Post by macrolime »

I asked ChatGPT if it has any technological applications. No ideas if its just bullshitting

Retrocausality, or the idea that events in the future can influence events in the past, is a concept that challenges our conventional understanding of time and causality. Although it is an intriguing concept that arises in some interpretations of quantum mechanics, it is important to note that there is currently no experimental evidence supporting retrocausality.

As a result, it is difficult to predict how retrocausality could be influenced or used in technology, since we have no concrete examples of retrocausality occurring in the physical world. However, we can speculate on how such technology might work if retrocausality were indeed possible.

    Communication: If retrocausality were real, it could potentially be harnessed for faster-than-light communication or even communication with the past. Such technology might allow us to send messages or information backward in time, which could have a significant impact on how we understand and interact with our own history.

    Computing: Retrocausal computing could theoretically be used to perform complex calculations more efficiently by taking advantage of future outcomes or solutions to influence the computational process in the past.

    Energy production: If retrocausality could be controlled, it might be possible to harness energy from future states of a system and use it to power devices or processes in the past.
However, it is important to reiterate that these applications are purely speculative and based on the assumption that retrocausality is a real phenomenon. Until there is experimental evidence supporting retrocausality or a more comprehensive understanding of how it might work, it is unlikely that we will see any practical technologies utilizing this concept.

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

#97

Post by a257 »

soperj wrote: post #90
Nevermark wrote: post #72

Earlier quoted context omitted.

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. 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)

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

#98

Post by causality0 »

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…

The sun being classified as a yellow dwarf does not mean it's "only yellow hot". You can observe that by going outdoors and holding up a white piece of paper and noting it is not yellow in sunlight.

powered by a nuclear explosion

Not quite accurate. The nuclear fusion going on inside the sun's core is not an explosion. In a nuclear explosion, a significant fraction of the fuel in a given area is consumed in an instant. The sun's core on the other hand only fuses its fuel extremely slowly. Pound for pound, the sun's core generates less heat energy than mammalian muscle tissue. It's just that there's so much of it that the heat energy is extremely well insulated.

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

#99

Post by layer8 »

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?

Several things:

– The laws of physics are essentially time-symmetric, and they have no concept of causation or of a preferred direction of time. In principle, the future causes the past as much or as little as the past causes the future. Physics effectively only says they have to be consistent with each other, as related by the laws of physics.

– The apparent directionality of time that we perceive is suspected to be tied to the entropy gradient we are on. See the “past hypothesis” for example [0].

> 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?

– I would say that all moments in time are equally real, including our consciousness at any given moment. There is no actual flow or “travelling”. The flow we perceive is merely an illusion caused by the fact that we only remember the past and not the future (which again may just be a consequence of the entropy gradient we are on). This is known as the “block universe”, or as “eternalism” [1]. The opposing view that only the current moment is real, and that the future differs from the past in its “realness”, is known as “presentism”.

– Note that any notion of “travelling” through time implies that you can draw a 2D diagram of where in time you are at each point in time, or which point in time is “real” at which point in time (in the sense that a moment in time isn’t real until time reaches that moment, but after that it is real and cannot be made unreal again), thus implying two dimensions of time. That doesn’t make any sense, and thus my personal conclusion is that the “presentism” view is nonsensical.

[0] https://en.wikipedia.org/wiki/Past_hypothesis

[1] https://en.wikipedia.org/wiki/Eternalism_(philosophy_of_time...

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

#100

Post by figassis »

__MatrixMan__ wrote: post #84
quijoteuniv wrote: post #76

Earlier quoted context omitted.

You can wish yourself well in the past. I believe this works.

I think of personal growth as a conspiracy between present me, past me, and future me. Where our motives are aligned, good things happen.

Allow me to steal this bit of insight
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