Quantum Gravity and time's arrow

hatfarm
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So, a couple weeks ago I read this article. I came here, expecting that someone would probably talk about it (I've been viewing posts here for a while, but became a member only recently). No one, that I could find, has actually talked about it, so I though it would be a good first post for me :). Here's the actual http://arstechnica.com/science/news...-everything-by-ditching-tenet-of-physics.ars" to the article which talks about two papers that utilize the recent finding of space-time behaving as if it has two dimensions at small scales. This allows space to be 1 dimension and time is the other. When you do this, space is the same along all paths, but time isn't (I don't know why, and can't read the actual papers).

This got me thinking about what I was thinking when I first read Brian Greene's "The Fabric of the Cosmos," why does anyone assume that time should be the same forward and backward? Have we ever observed it to be so? I will agree that there are times when it is possible to take a small slice of space-time and not be able to tell the difference forward or backward in time. Like watching a fan move, you wouldn't necessarily know which way time was pointing initially. But this isn't true of all of space-time, space is, but it certainly isn't the same when you put time in there. It seems to me like a way of sticking to classical physics where everything is just a bit easier.

I'm no physicist, actually really just getting started in my physics education, and I'm only going to minor in it, so I don't really know how many people assume that time should be the same both ways. That is something that Brian Greene posited in that book though, and it just struck me as odd, since science is supposed to be used to explain observations and I've never heard of anyone observing that. Perhaps I just misunderstood what he was trying to say, but I just had to ask to make sure.
 
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Wow, can't believe I missed that... sorry. Thanks!
 
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. Towards the end of the first lecture for the Qiskit Global Summer School 2025, Foundations of Quantum Mechanics, Olivia Lanes (Global Lead, Content and Education IBM) stated... Source: https://www.physicsforums.com/insights/quantum-entanglement-is-a-kinematic-fact-not-a-dynamical-effect/ by @RUTA
If we release an electron around a positively charged sphere, the initial state of electron is a linear combination of Hydrogen-like states. According to quantum mechanics, evolution of time would not change this initial state because the potential is time independent. However, classically we expect the electron to collide with the sphere. So, it seems that the quantum and classics predict different behaviours!

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