Mind Matters Natural and Artificial Intelligence News and Analysis

TagTime travel paradoxes

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Time concept. Hi-res digitally generated image.

A Form of Time Travel That Might Be Possible…

In world of entropy, time runs in one direction and reversing it would create impossible contradictions. physicists say

Of the four dimensions, only time is mysterious. We can play games with the other three, the spatial dimensions — imagining, for example, 2- or even 1-dimensional universes, as in Flatland (1884). But in the end, they follow the rules. Time goes in one direction only and time travel — moving time in the other direction is easy to imagine in principle but full of nearly impossible conundrums in practice. Astrophysicists struggle to figure it out. Our brains are adapted to keeping track of the present (the experience of “now”) and the past (memory). But that only tells us how we come to be aware of time. It doesn’t tell us what time is. We get a bit closer, says…

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Twisted clock face. Time concept

The Central Mystery of the Universe Is Time

Physicists assume everything is reversible in principle — yet time isn’t. Why not?

Physicist Paul Davies unpacks it, so far as anyone can: Physicists first got to grips with the problem of the arrow of time in the middle of the nineteenth century by considering the behavior of gas molecules rushing around and colliding. Imagine a box of gas with a barrier down the middle. Suppose the gas on the left is hotter than on the right. If the barrier is removed, the faster-moving molecules on the left collide with the slower ones on the right, redistributing the energy. Soon the gas reaches a uniform temperature, a condition known as thermodynamic equilibrium. This process is irreversible. You never see the opposite happening. Without external interference, heat always flows from hot to cold. It’s…

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Science fiction illustration of a battle cruiser spaceship travelling faster than the speed of light in hyperspace, 3d digitally rendered illustration

What If a Loved One Aged Much Faster Than You? – Sci-fi Saturday

It’s one of the implications of faster-than-light travel

“ARK” at DUST by Nelson Cruz (June 8, 2021, 8:19 min) “Captain Mira Bernhard is finally home after a lengthy mission to the new planet, GAIA – humanity’s last hope. But what’s only been a 5-year trip for her, has been 45-year wait for her husband.” Review: ARK debuted in 2020. Time, we are told, is running out for Earth. The radio announcer, informing the audience of Bernhard’s ship’s arrival, also announces that this will be the final week of broadcasts. We are told that Bernhard’s husband Peter (played by Patrick Gorman) does not know what to expect. But, of course, he really does. And he faces a big decision: Should he just free her (Sheila Cutchlow) to return to…