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Reality doesn’t exist until it is measured, quantum experiment finds

anu.edu.au

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Re: Reality doesn’t exist until it is measured, quantum experiment finds

#211

Post by madaxe_again »

orbifold wrote: post #181
madaxe_again wrote: post #142

Earlier quoted context omitted.

I came here to say the same thing - this behaviour is readily explained by a pilot wave formulation of QM, and requires no spookiness. Increasing number of physicists are re-evaluating Bohm and De Broglie's work - I for one think we've been down a 60 year dead-end, which has yielded models , but no plausible mechanism.

I'm fairly certain that you would have a very hard time extending pilot wave theory to Quantum Field theory, although who kowns, maybe it is possible.

It can be - did a graduate paper on the topic some years ago, looking at it through the Dirac sea - and appears others are taking an interest in the topic too - here's a nice paper which gives a good overview:

http://iopscience.iop.org/1742-6596/306/1/012047/pdf/1742-65...

Re: Reality doesn’t exist until it is measured, quantum experiment finds

#212

Post by themgt »

dmvaldman wrote: post #116
themgt wrote: post #32

Earlier quoted context omitted.

Right. This way of describing it is much closer to "zero-worlds" or relational quantum mechanics, and to my mind is a far simpler, deeper way of understanding what's really going on - reality is simply all entanglement. What really still gets me is the way it's not simply that the atom wasn't interacted with, but that if the information about the interaction never leaks to the outside world - if it's "erased" after t…

Do you have a source for this "information leaking" concept. I remember hearing about an experiment confirming such an idea, but I can't recall what it was.

I'm not sure the exact experiment performed in the article (which sounded similar), but I've always thought the delayed choice quantum eraser was about the best example of this, once you spend some time understanding the experiment and results:

https://en.wikipedia.org/wiki/Delayed_choice_quantum_eraser

Re: Reality doesn’t exist until it is measured, quantum experiment finds

#213

Post by hagmonk »

paraiuspau wrote: post #111
yummybear wrote: post #95

Earlier quoted context omitted.

Reality frustrum culling?

^ This

I kind of love the idea that it's an optimization because the universe would have a shitty frame rate if light's quantum state wasn't lazily evaluated based on whether anyone's viewport was aimed at it.

Re: Reality doesn’t exist until it is measured, quantum experiment finds

#215

Post by eli_gottlieb »

rbanffy wrote: post #59
marwatk wrote: post #25

Earlier quoted context omitted.

I've always wanted to read (or write?) a book about us determining we are in a simulation, but we find subtle flaws like this we're able to exploit in weird ways. Kind of like breaking out of a VM through register flaws or something. Anyone know of a story along those lines?

I think Charlie Stross did a particularly interesting one that happened within a simulation where the characters ultimately discover the enemy they were fighting already won and their simulation ran under a larger simulation. Can't remember the name...

Sounds like the ending to A Colder War.

Re: Reality doesn’t exist until it is measured, quantum experiment finds

#216

Post by eli_gottlieb »

dghf wrote: post #210
eli_gottlieb wrote: post #200

Earlier quoted context omitted.

Proposition (2) is just flagrantly, blatantly bullshit. The amount of computational power needed to simulate even just the bits of the universe we conscious humans happen to be observing at any one time is so stupendously humongous that you'd get more utility out of repurposing your cosmic-scale computers to play video games.

Erm, doesn't that mean you actually agree with proposition (2)? > (2) any posthuman civilization is extremely unlikely to run a significant number of simulations of their evolutionary history (or variations thereof) [Emphasis added.]

Errr, yes, I misread the phrasing. Yes, I think a decently posthuman civilization is not going to be able to defy the laws of physics in such a way that would make it economical to run ancestor simulations.

Re: Reality doesn’t exist until it is measured, quantum experiment finds

#217

Post by david927 »

Ygg2 wrote: post #187
david927 wrote: post #184

Earlier quoted context omitted.

I will happily imply that energy/mass cannot move faster than light. You know, I think a hidden variable theory is a crutch. To me, there's simply a Planck's constant foundation that prevents infinite regression just as much in terms of information as it does with radiation, etc.

What you imply is besides the point. It's what the finding implies. Interpreting that as "physical reality doesn't exist" is far fetched.

This isn't about relativity at all.

If you're measuring N-S electron spin, you will get 100% N spin or 100% S spin but never any E-W spin. Period. If you're measuring E-W electron spin, you will get 100% E spin or 100% W spin, but never any N-S spin. You can word smith it how you wish, but electron spin is directly tied to the spin you look at. To speak of the "reality" of the spin when you're not measuring it makes no sense.

Re: Reality doesn’t exist until it is measured, quantum experiment finds

#218

Post by nicwolff »

TheOtherHobbes wrote: post #168
antimagic wrote: post #154

Earlier quoted context omitted.

I always find it fascinating at just how much of our fundamental physics ends up being constraints on information movement. The laws of thermodynamics are about entropy, general relativity puts constraints on the movement of information (for example, Spooky Action as a Distance(tm) is faster than light, but you can't transmit information with it), the Uncertainty Principle puts limits on how much information you can…

It's hard to imagine a universe with infinite resolution. You'd effectively have an infinite number of bits in an infinitely dense space, which would potentially require infinite energy to flip. But I suspect (on no basis whatsoever, except the fact that all previous metaphors have been wrong) that the "universe = Turing machine model" is wrong in some fundamental ways. I have no idea what the universe is, but I'm op…

Quantum loop gravity theory suggests a resolution of 1.61619926 × 10^-35 meters, the Planck length.

Re: Reality doesn’t exist until it is measured, quantum experiment finds

#219

Post by colomon »

shiggerino wrote: post #146
reinhardt wrote: post #105

Earlier quoted context omitted.

Not really, most of it is just hacked together with perl: https://xkcd.com/224/

Perl 6 has lazy evaluation, doesn't it?

Lazy lists, anyway. As far as I know there's no built-in support for lazy scalar evaluation.

Re: Reality doesn’t exist until it is measured, quantum experiment finds

#220

Post by Kequc »

dghf wrote: post #209
Kequc wrote: post #196

Earlier quoted context omitted.

The topic outlined in the OP's article has been raised before, multiple times, once every couple of years. It was even the focus of a cult indoctrination propaganda piece called "what the bleep do we know". http://skeptico.blogs.com/skeptico/2005/04/what_the_bleep_.h... Essentially, yes, it's bogus science. Quantum physics are much more complex than these articles ever bring on. But by explaining it simply, it sounds…

> It isn't that particles exist in multiple states until they are measured. I thought it was exactly that. Or rather, particles exist in multiple states, and when they are measured, either those multiple states collapse into one (Copenhagen Interpretation) or you, the measurer (who also exists in multiple states), gets entangled with them, causing each of your states to perceive exactly one of the particles' states (…

I'm personally a really big fan of the Many-Worlds Interpretation. Because a brief abstraction would mean every person will live as long as is physically possible. To outside observers, you may have died at any point along the way.

https://en.wikipedia.org/wiki/Quantum_suicide_and_immortalit...

But, regardless. The copenhagen interpretation is from the 1920's. That isn't to say it's wrong, it's just out of date. It has been expanded upon or replaced since then so why hold onto it, what is the current understanding.

The most important takeaway here is that since measuring very small things affects its outcome, it is currently impossible to know. Articles like this one in the OP bother me because they don't know either. But it always becomes a sensation and spreads misinformation.

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