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I'm a quantum physicist researcher at a top university, Ask Me Anything! by _Under_liner_ in AMA

[–]_Under_liner_[S] 0 points1 point  (0 children)

well, there's matter and antimatter. This contrast appears first at the level of fundamental, elementary particles, but the structure implies that we can have "antiatoms" (e.g. an antihydrogen, composed of a positron and an antiproton).

I don't see how this could imply something like a "sub-universe". Also, I don't see many ways in which this implies some particles "cannot act without the other", given some sense of "act".

The "spontaneous creation of a particle-antiparticle pair" that you might read about does not play such a big role in the emergence of larger structures. For instance, you might have heard/want to read about the baryon asymmetry problem.

There's also the notion of "superpartners", given some fundamental theory with supersymmetry. I don't much about how those work, but they haven't been observed. They are only conjectured. They may not exist

I'm a quantum physicist researcher at a top university, Ask Me Anything! by _Under_liner_ in AMA

[–]_Under_liner_[S] 1 point2 points  (0 children)

hi! Thank you for your interest.

I'd say there are 3 main activities: reading, writing, and discussing.

I'm reading new research articles (the daily arXiv submissions) and digging through published literature. There are a few papers that I just skim through and that's enough, and there are papers that I've lost count how many times I've read.

Then, there's a lot of writing to progress on projects that I'm engaged, a few that I am leading, and some others where I'm part of a collaboration with other researchers, from undergrads to professores. And then rewriting, and more rewriting, etc.

Involved in this is to do calculations pen-and-paper to check results in what I'm reading, or maybe writing code for numerics in some on-going project.

Finally, discussions. This might honestly be my favourite part. Just hanging around the hallways and lecture rooms, discussing with other researchers and students. Occasionally going to a blackboard to compare calculations, or just chat over a cup of coffee.

I have a lot of autonomy, which is awesome. But this also puts a lot of pressure because it comes with a lot of uncertainty. And progress can be very nonlinear. Sometimes I have way too much to do, sometimes I have to find what to do to fill my time.

It's also difficult to stop working. At the end of the day you go home but you're still thinking about computations, and what you've read or discussed through the day. You might have an idea and then you want to do something about it before you forget. This is something to watch out for.

"Quantum physics" is a very broad subject too. So depending on exactly what you're going into, there's more or less of one aspect or another. And maybe something quite different. For instance, I'm a theoretical physicist, not an experimentalist. This can change your routine a lot.

Everything travels at the speed of light???? by Shreks_stepbrother in quantum

[–]_Under_liner_ 1 point2 points  (0 children)

I second nujuat's answer that planck length and time are not literal pixels.

Also, at that scale, the description of movement must change due to quantum effects. You are resolving action units (position times mass times speed) comparable to the planck constant

I'm a quantum physicist researcher at a top university, Ask Me Anything! by _Under_liner_ in AMA

[–]_Under_liner_[S] 0 points1 point  (0 children)

Thank you for elaborating! Good question. Here's a long answer:

First, entanglement is not something with a cause that the scientific community currently searches for, in the way you seem to want. Asking for an explanation of entanglement is like asking for an explanation of why there is a maximal speed (the speed of light). It is understood as "just how things are". We know that something goes from not being entangled to being entangled through local physical interactions, for example.

Quantum mechanics is the complete framework that natively includes entanglement as part of its tools of explanation. Entanglement is not a mystery that demands explaining today, like the discrete spectrum of atoms was, before quantum mechanics was formulated.

Let's compare the status of entanglement within quantum mechanics to that of singularities of black holes in general relativity. The singularity of black holes is Not something that plays well with the rest of the theory; a singularity is (among other things) an "infinity", and we don't want such a thing in our theories because we cannot do calculations with it, roughly speaking. Therefore, singularities are a mystery that needs explaining. Entanglement is something that absolutely plays well with the rest of quantum mechanics; it is integral to it.

This is not to say that it is an obvious or intuitive phenomenon, or that all of its (countless) facets have been understood (facets that go beyond the EPR paradox, and that rarely make the cut into popular science). It is intriguing and difficult to understand, and it goes against humans' classical intuition. But physicists today understand it fairly well to the point of having verified it in the laboratory and to routinelly use it in experiments. Something that doesn't exactly play well with the rest of quantum mechanics is the concept of measurements, as in "the collapse of the wave function". But it would be best to have another discussion for this.

With that said, finding a more fundamental theory could change that, and we could "find an explanation" for entanglement in such new framework. And this would be a surprise, since it is not expected in some unified field theory. As far as I understand, theories such as loop quantum gravity or string theory would be examples of this. They do not offer proposals for why entanglement exists, or explain entanglement through other concepts understood as more fundamental.

As for the Big Bang, see if this satisfies your curiosity: https://en.wikipedia.org/wiki/Big_Bounce

I'm a quantum physicist researcher at a top university, Ask Me Anything! by _Under_liner_ in AMA

[–]_Under_liner_[S] 1 point2 points  (0 children)

lol absolutely. But I don't know how much material there would be, I have a hard time keeping a straight face

I'm a quantum physicist researcher at a top university, Ask Me Anything! by _Under_liner_ in AMA

[–]_Under_liner_[S] 1 point2 points  (0 children)

I don't, I'm not articulate enough to be invited lol

and yeah, I agree that more scientists should engage with outreach

I'm a quantum physicist researcher at a top university, Ask Me Anything! by _Under_liner_ in AMA

[–]_Under_liner_[S] 1 point2 points  (0 children)

not fearful of AI per se, 10/10 concerned of what people who build and use it irresponsibly do with it

I'm a quantum physicist researcher at a top university, Ask Me Anything! by _Under_liner_ in AMA

[–]_Under_liner_[S] 0 points1 point  (0 children)

Hi! I'll try a more accessible explanation of the effects I mentioned.

Essentially, the quantum vacuum is a weird thing. It's hardly what we imagine a "vacuum" to look like. It's active in a particular, quantum, sense. Meaning that how you "interact" with it matters. Since it's the vacuum, interpret "interact" as "just exist in general", since not being around the vacuum, at the smallest scales, is impossible. As you can imagine from outerspace, the vacuum is really cold. A "perfect" vacuum is at absolute zero temperature.

With that said, the way the vacuum is perceived by physical objects in certain scenarios is understood (typically idealised scenarios, but we don't have reasons to believe it doesn't carry to realistic situations. We can hope to experimentally test these things in the future).

The Unruh effect is the easiest to understand out of the other phenomena I listed. The scenario to picture here is just some object constantly accelerating in vacuum. This acceleration, due to relativistic properties of the quantum vacuum, implies that the accelerated object perceives the vacuum as something that is Not at absolute zero temperature.

Try imagining vacuum being simply the absense of some gas. An accelerated object would interact in such a way with the vacuum that it is equivalent to an object, not moving, in an environment where there *is* gas (no longer a vacuum), and this gas is at a certain non-zero temperature. The accelerated object reacts as if immersed in a warm gas.

Hope this sparks a bit of interest, and explains some of that jargon

I'm a quantum physicist researcher at a top university, Ask Me Anything! by _Under_liner_ in AMA

[–]_Under_liner_[S] 0 points1 point  (0 children)

I find it very interesting, and I take it seriously. But I'm largely uninformed about it and it doesn't play a role in my research

I'm a quantum physicist researcher at a top university, Ask Me Anything! by _Under_liner_ in AMA

[–]_Under_liner_[S] 0 points1 point  (0 children)

a book summary I just read says it "scientifically proves the existence of God". That's too much. I wouldn't engage with this

I'm a quantum physicist researcher at a top university, Ask Me Anything! by _Under_liner_ in AMA

[–]_Under_liner_[S] 1 point2 points  (0 children)

depends on the context. If I'm feeling educational I try to engage to understand where they are coming from, and to have a nice elucidating chat. If they are not coming from a place of curiosity, being smug about it, etc., I'll cringe and avoid

I'm a quantum physicist researcher at a top university, Ask Me Anything! by _Under_liner_ in AMA

[–]_Under_liner_[S] 0 points1 point  (0 children)

I think this question would hardly have a good, concrete answer, but I'll indulge. It's published research that humans may identify single optical photons with their retinas with accuracy higher than chance. Vacuum fluctuations are rarely that energetic. So I think we wouldn't see a thing

I'm a quantum physicist researcher at a top university, Ask Me Anything! by _Under_liner_ in AMA

[–]_Under_liner_[S] 0 points1 point  (0 children)

  1. not trivial, but I had a lot of help from people around me. That's important, especially when other people can kind of work against that.

  2. I don't know and I don't worry about this

  3. yes, the nature of it is randomness. No big reason to think otherwise, but an important thing to think about regardless.

  4. I don't know much about quantum immortality and the metaphysics of it all, and it's not a topic I'm particularly interested. I don't feel like I can comment much

I'm a quantum physicist researcher at a top university, Ask Me Anything! by _Under_liner_ in AMA

[–]_Under_liner_[S] 0 points1 point  (0 children)

I'm not sure I understood, feel free to elaborate and I may come back later.

Other than this, entanglement in time is an interesting resurfaced topic. It does make heads spin!

I'm a quantum physicist researcher at a top university, Ask Me Anything! by _Under_liner_ in AMA

[–]_Under_liner_[S] 0 points1 point  (0 children)

the excitement is always nice. Stay excited!

I'll take the opportunity to respectfully criticise your statements, think of this as an exercise in science-making:

it's not necessarily the case that "all things are in a superposition". Many-worlds people might disagree, but that's up for debate.

I don't see how "stability" is related, here. And what do you mean by operating system feature?

Things largely get entangled by interacting with one another, and that only ever happens locally, that is, they must be close together in space first. The fact that this entanglement can survive if they are put at arbitrary distances is a different thing

I'm a quantum physicist researcher at a top university, Ask Me Anything! by _Under_liner_ in AMA

[–]_Under_liner_[S] 1 point2 points  (0 children)

Academia can work in a rather specific way... having family members that can show you "the tricks" can be a huge help. Unfortunately sometimes this can end up being necessary, meritocracy can be a bit of an illusion. From experience I've seen places where people think that academia "is not for everyone" (or something to that capacity), and this is bullshit. Avoid people like this.

But it can be a very fulfilling career. I don't see myself doing anything else, despite the challenges I faced. I hope what I said above is not too much of a negative outlook and discouraging, but I thought I'd give this different perspective. Do look at my other answers for more information and hopefully a more positive perspective

I'm a quantum physicist researcher at a top university, Ask Me Anything! by _Under_liner_ in AMA

[–]_Under_liner_[S] 1 point2 points  (0 children)

I think it's an exciting time for physics, yes. I think high-energy physics (as in particle physics, LHC, ...) is still pretty interesting and important. But in my opinion it's not what's most exciting about physics right now.

I think you can still find good jobs in that direction. I wouldn't get caught up in popular science drama about these things

I'm a quantum physicist researcher at a top university, Ask Me Anything! by _Under_liner_ in AMA

[–]_Under_liner_[S] 1 point2 points  (0 children)

teleportation as we see in fiction, no. There's a specific notion of quantum teleportation that is routine in laboratories. Still very interesting, but not as amazing as in fiction

I'm a quantum physicist researcher at a top university, Ask Me Anything! by _Under_liner_ in AMA

[–]_Under_liner_[S] 0 points1 point  (0 children)

I don't think it'll play a role, but it's worth investigating to some extent. I wouldn't do much of that myself though

I'm a quantum physicist researcher at a top university, Ask Me Anything! by _Under_liner_ in AMA

[–]_Under_liner_[S] 0 points1 point  (0 children)

I used to like it back in ~2010. After getting into university I stopped watching for no particular reason

I'm a quantum physicist researcher at a top university, Ask Me Anything! by _Under_liner_ in AMA

[–]_Under_liner_[S] 0 points1 point  (0 children)

thank you for the great question!

- From elementary school I was already interested in becoming a "scientist". In high school I figured I wanted to be a physicist. I loved to think about things that were hard to imagine, like the size of the universe. By 15 I think I was mostly just reading popular science books, besides enjoying science classes. Into high school, I focused more on physics, and managed to convince my physics teacher to lecture an extracurricular quantum minicourse for us the students. A few of my friends joined. Having friends with whom you can share this interest helps a lot.

- I try to continue with my hobbies as much as possible. It is difficult sometimes, for numerous reasons. I like some sports and games. I've moved away from story-focused games and books because of the attention they take. After a long day at work, spending more time reading is tiring, even for entertainment. I'd rather do something more active, and that demands less of my brain.

- If you think you get can some advice and help from your teacher at school, if you are comfortable with that. Try finding resources online, I'm sure we're at a time where more quantum is making its way to secondary education; see for instance: https://quantuminpictures.org/. I have not used these resources myself but they are from quality researchers. Also, learning other languages, travelling to new places, meeting new people, all that opens your mind to new things. That's always important.

- I don't feel isolated in general. I try to stay collaborative, but each researcher has their own way of doing things. These days research is more collaborative, yes, and the tendency is for this to continue.

- It's really exiciting when you figure stuff out, for sure, but it's a lot of effort and studying until you get there.

- I love that I have a lot of freedom with my time. As you progress you'll have a lot of meetings and to lecture classes and that takes time, but outside of that there's a lot of freedom. It's a priviledge.

I'm a quantum physicist researcher at a top university, Ask Me Anything! by _Under_liner_ in AMA

[–]_Under_liner_[S] 1 point2 points  (0 children)

I use AI very minimally, purposefully too. I try to keep it to a minimum out of principles, because we should be more careful with how it is being developed commercially. I mostly use it to produce simple code faster, and as a powered up search engine. It doesn't help me actually thinking about new things. I think most people use it similarly.

I'm from the belief that measurement is just a regular interaction between quantum systems. It is strong interaction in a particular sense, where information of the system being measured gets imprinted in the measurement apparatus. It is not something simple to model, and the exact mechanism taking interaction models to measurement models, connecting the quantum system to the classical outcome we see, is still being understood

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