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by alexawarrior 1086 days ago
In string theory, which is a branch of theoretical physics, there's an idea called "mirror symmetry." This suggests the existence of two parallel worlds (let's call them A-side and B-side) that are very similar but have certain differences in how their internal six-dimensional spaces are structured (we'll call these spaces A and B).

Until now, we've learned a lot about space A. In particular, we've found that it doesn't undergo extreme changes (or "blow up") under certain conditions. Recently, scientists noticed that spaces A and B can change in certain ways so that objects in them that seem different at first can end up looking the same.

In this research paper, the authors investigated whether space B behaves in the same way as space A. They took a phenomenon that we know happens in space A, moved it over to space B, and checked whether it still works the same way. They found that just like in space A, no blowing up occurs in space B under certain conditions.

This is a big deal because it gives mathematical proof for a similarity between the A-side and B-side that scientists had previously only guessed might be true. To prove their theorem, the authors had to make some assumptions, but in future work, they'll see if their theorem still holds true even without those assumptions.

So in a nutshell, they're trying to explore whether certain properties of one world in string theory also hold true in its "mirror" world. They've found evidence for this in one specific case, but there's still more work to do.

2 comments

Theoretically, would the world we can observe live in only one of these spaces (and if so, which one) and there would be an alternate reality or are these spaces intrinsically linked to each other?

How does this interact with quantum mechanics? Would spaces A and B evolve differently over time depending on the randomness of quantum behavior or are the outcomes of quantum interactions shared between both spaces?

And I would add to that, much hype notwithstanding, we have no real evidence for string theory.
> ...we have no real evidence for string theory.

Because we cannot experiment with items that are so small.

However...

Science has thrown math at the theories of strings and the math tends to work out. The models we've built tend to confirm it.

At one time mankind didn't believe in unseen 'creatures' that made one sick. At one time mankind didn't believe in anything we cannot see, and yet we have infrared detectors, xray detectors, photon detectors, etc...

No proof doesn't mean shit in science, it only means we haven't been looking long enough or hard enough, or we don't have the right tools /at the moment/ but perhaps in the near future.

Here's a bit of a primer:

> https://www.space.com/17594-string-theory.html#:~:text=Has%2....

…or that we’re inventing epicycles, again.

Science is full of ideas that work out mathematically but were supplanted by a better model (epicycles) or refined when their predictions didn’t match reality (ethers).

String theory could easily be that; we didn’t find super-symmetric pairs at the LHC.

More epicycles are needed!

> Science is full of ideas that work out mathematically but were supplanted by a better model (epicycles) or refined when their predictions didn’t match reality (ethers).

Honestly I think this is even true of much of our current understanding of physics. People take it for granted that we've discovered some irrefutable facts, but there is so much we don't know and understand.

It's entirely possible while the math checks out currently for our theories, they could be way off in many ways.

String theory hasn't been able to reproduce either the Standard Model or General Relativity. They have lots of arguments for why they should, but they can't even come up with existing physics, let alone predict anything that can be tested.

This after around 40 years of work.

We have no real evidence because it can't even make a prediction that could be tested.

Math and models will work on as many theories as you want when all the theories make the same predictions.