/r/HeKnowsQuantumPhysics
Links to people making incorrect or overconfident statements about quantum physics on reddit.
Links to people making incorrect or overconfident statements about quantum physics on reddit.
Most links are submitted by /u/Cohen-Tannoudji (a joint mod account), but this is by no means a rule. All contributions are welcome.
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/r/HeKnowsQuantumPhysics
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Space and time cannot be infinitely divided. So time can only be broken up into a finite number of individual frames, and space can only be broken into a finite number of individual pixels or locations that matter can occupy or be composed of inside of that space. So things don't move smoothly through space through an infinite number of positions, they actually move through a finite number of frames and pixels where there are very small quantum jumps that occur between those frames and pixels.
I'm basing this off of Planck length and Planck time. I'm talking about how long it takes light to travel across a Planck length which could be considered a single "frame" of time. This is the point that is reached where no more frames can be placed between the existing frames. So if you were going to take a bunch of individual pictures or frames of somebody walking across the room to make a motion picture or flip book or something, there are only so many pictures that could be taken during that time even if the camera speed was not an issue. A point is reached where there are very small quantum jumps that happen between one Planck length to the next, as if our reality is pixelated or something. Their motion cannot be infinitely divided.
You can divide time on paper as far as you want to go, but that doesn't mean you can do that in reality. This has to do with motion, and measuring time with motion or distance traveled. So imagine if you could freeze everything in place in a moment in time and take a picture of it, what I am talking about is the shortest distance that any of those things could travel before it could be frozen again and another picture could be taken.
Let me give you an example to help you better understand what is actually happening. A Planck length is the shortest distance that space and time can be divided into, so imagine that you have a piece of matter that is in motion and is exactly the same size or dimensions of that Plank length. I like to imagine Planck lengths as pixels of space. So that pixel size piece of matter can never be half way inside of one Planck length of space and halfway in another, it has to be all the way in one or the other at all times. So it jumps from one pixel of space into the other as a whole and all in one motion instead of it filling that next pixel of space a little bit at a time. It completely leaves one pixel of space and completely fills the next one all in one instantaneous jump.
So there would be nothing different to take a picture of between those two pixels or frames in time, because nothing has changed until it has jumped from one pixel to the next. There would also be no time to take any identical pictures of that motion without stopping time somehow. So my question is, how would it be possible for an infinitely small and dense "singularity" to exist inside of space or composed of matter that cannot be infinitely divided?
There are two very good reasons that singularities can only exist as an idea and never in reality. One is the reason I already mentioned about Planck length, and the other is the fact that an infinitely small and dense singularity means that it could always get smaller and denser. So if you called something a singularity now, what should you call it after it gets smaller and denser, and at what point is it actually small or dense enough that you should start calling it a singularity instead of just something really small and dense?
There are a lot of people that make these wild and unjustified speculations that it is possible to squeeze space and matter so tightly that they stop existing, that they stop being space and matter, that matter starts magically occupying less dimensions, or that time and the laws of physics magically stop existing. Those ideas are just a bunch of unjustified science fiction BS that defy logic, and there is no actual evidence to support them being true.
People will point to math or physics equations as their "evidence" that singularities exist. To those people I would say that you must realize what math can prove and what it can't. There are a lot of things in math and physics equations that only exist as an idea or concept, but that don't actually exist in reality. Like negative numbers for example, since nothing can be less than zero in reality. Math and physics equations themselves cannot prove anything about reality. They can only prove things about your current model or understanding of this universe, and those calculations and equations can only tell you if that idea fits inside of your current model or understanding without contradicting what you think you know so far. It can't prove that your model itself that you are comparing it to is accurate and actually represents reality.
So I am not going to buy into the concept of singularities actually existing in reality and all the magic they propose that comes along with them, until they provide me with some actual proof or evidence other than just calculations or equations written on a piece of paper.
"Today's scientists have substituted mathematics for experiments, and they wander off through equation after equation, and eventually build a structure which has no relation to reality."
--- Nikola Tesla
Hi i am 18 and i have a question and i don't know much about quantum world but i love it i am way too much interested in quantum mechanics !!! My question is a bit silly i guess but things keep popping up in my mind...
My question is,
We know about positive and negative charges. So.. Can't there be a charge which behaves like both i mean some time's positive and some time's negative (dual nature)??
I'm really interested in quantum physics but from the books that I have found, a lot of them involve a lot math, and my mathematics level isn't there yet. What are some books which give a good foundation for the basics with little/some math?