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myridium

Re:Does superdeterminism save quantum mechanics? on Monday December 20, 2021 @03:25AM (#29622535)
It may be inadequate, but the consequences of quantum theory still apply without having to add new postulates. Among those consequences is many worlds.
Re:Does superdeterminism save quantum mechanics? on Monday December 20, 2021 @03:24AM (#29622528)
Except we do observe interference effects. I'm not sure what you mean.
Guess that's what happens when you shut down safe, cheap, emissions-free sources of electricity for nonsense ideological reasons (nuclear power plants).
Re:Does superdeterminism save quantum mechanics? on Sunday December 19, 2021 @09:06PM (#29620808)
I'll have to look into those derivations. Thanks.

> There is an additional postulate, namely that the state vector is the real world we inhabit.

Well, yes, it's a model for the physical world. Refusing to accept that the state vector is the real world we inhabit is tantamount to rejecting the existence of an objective universe, in which case any discussion is moot, or to the outright rejection of quantum theory, which seems irrational. (i.e. "I don't believe the state vector represents our world, despite it being the best physical model of our time")

Re:Does superdeterminism save quantum mechanics? on Sunday December 19, 2021 @08:58PM (#29620770)
In QM, evolution is unitary. The Born Rule is an empirical observation that is adequately explained by the decoherence of a quantum system into entangled states of observer, environment, measurement apparatus and the system being measured.

E.g. the master equation for a quantum density matrix governs its evolution when the environmental conditions are not completely known or modelled. Classical ensembles or 'decohered' states occur as a consequence.

QM is formulated as a deterministic theory. When you try to model an open, interacting system without tracking its environment, you have to sacrifice determinism in that model, because you are failing to track all the information in the system. You settle for probabilistic quantities. Nothing quantum about it either-- same thing happens in classical mechanics. They call this "classical thermodynamics".

Re:Does superdeterminism save quantum mechanics? on Sunday December 19, 2021 @08:52PM (#29620739)
Of course. I assume that in those papers, she demonstrates a similar lack of understanding of the details. Or that she doesn't research on quite the same things she talks about in her public-facing content.

Someday I'll get around to reading some of them, and I'll find whether that assumption is wrong.

Re:Does superdeterminism save quantum mechanics? on Sunday December 19, 2021 @08:47PM (#29620708)
I didn't commit an ad hominem fallacy. I did not say that her blog is invalid because of her character. I was just commenting on her character (actually more so on her work tbh).

i.e. an insult is not an ad hominem. This is an ad hominem: "Your argument is wrong because <insult to character>." This is not an ad hominem: "<insult to character. Particularly an insult that they often wrong>"

Re:Does superdeterminism save quantum mechanics? on Sunday December 19, 2021 @08:46PM (#29620700)
Nobody does that. We follow the math and the experimental results. There is friction against accepting what the results tell us, which is the odd thing.
Re:Does superdeterminism save quantum mechanics? on Sunday December 19, 2021 @07:52PM (#29620363)
You're exactly the target audience for her content :) .
Re:Does superdeterminism save quantum mechanics? on Sunday December 19, 2021 @07:47PM (#29620336)
Why is GR required? Already in standard QFT (Minkowski metric; flat spacetime; special relativity) the propagator 'violates causality'. Although that phrasing is misleading; it doesn't mean there's any logical inconsistency.

'The future affects the past' you might say. Yes, well, all information about the future is derivable from information about the present. So actually those 'future influences' are determined by the present. In the same way, 'locality' is almost a moot concept, because the analyticity of fields implies that the value of fields at remote locations is determined entirely by the field locally.

Re:Does superdeterminism save quantum mechanics? on Sunday December 19, 2021 @07:35PM (#29620257)
> Superdeterminism, arguably misnamed, simply argues that QM is deterministic

This is incorrect. QM is already deterministic. Where oh where do people get the idea that it is not?

Re:Does superdeterminism save quantum mechanics? on Sunday December 19, 2021 @07:28PM (#29620213)
Well if they insist on expressing the dynamics of the universe as the minimisation of a global (or local) action functional, then they are already throwing in the towel because that implies a wavefunction of the universe.

I'm suspicious that these fringe quantum-physics-deniers just don't understand the mathematics. They want to be relevant but they don't want to learn, so they post wordy, fluffy blog posts targeted at non-professionals. Like Sabine.

Re:Does superdeterminism save quantum mechanics? on Sunday December 19, 2021 @07:26PM (#29620196)
Totally agree. It's therapeutic to read this.

Last I checked, many-worlds is a consequence of current quantum theory, not a postulate or additional axiom. Yet people treat it like such. Probably because it's 'spooky'. Then indeed it's ironic that they search for alternative explanations which try to say the same thing as many worlds but without saying 'many worlds'.

Re:Does superdeterminism save quantum mechanics? on Sunday December 19, 2021 @07:19PM (#29620135)
Well if you're doing fermionic thermal field theory sure (where the `integral' on Grassmann numbers is just some linear operation which satisfies certain properties). But apart from that I thought all the thermodynamic quantities were defined in terms of the partition function, which is a perfectly well-defined (Riemann) integral...
Re:Busy Simulator: Feign importance with repeating app sounds on Wednesday December 15, 2021 @03:58AM (#29563548)
Nice concept, but the sounds are audibly not Poisson-distributed. Rookie mistake.
Badge of honour I'd say. What was your transgression?
Any ideas on how to short the economy for the inevitable repeat of the GFC?
Whatever benefit you perceive in gaming the current inflation rate is most likely cancelled by the massively inflated house prices from everyone else having the same idea. Market is efficient, remember?

So you sold the bank a bond with an inflated par value, figuring interest rates will rise soon (lowering the bond value) and snatched a good deal. Except the banks are almost certainly better at predicting the future interest rates, and they demand a coupon rate significantly higher than the risk-free rate to compensate.

The short of it is that the banks aren't stupid; the potential for a future interest rate hike is priced in.

The exception is if the banks are selling on their mortgage bonds to someone else-- then they don't care if they're paying too much for them, and they'd be happy with the additional demand.

Isn't that how the 2008 Global Financial Crisis happened...?

Re:Ask HN: Is passwordless login a good idea? on Tuesday November 23, 2021 @05:33AM (#29316320)
You should be using the accepted FIDO2/WebAuthn standard https://github.com/passwordless-lib/fido2-net-lib
Ah, so a US citizen living in the middle of nowhere learned something by seeing civilisation. This is an example of why the OP asked for more details. Now I know that your experience isn't applicable to a lot of people who already live in a city, have friends in other countries, have travelled a bit, etc.
Re:How 2 Billionaires Feel About Bitcoin Previously on Wednesday March 10, 2021 @09:10AM (#26411362)
I mean they're not wrong, even today.
Re:Ask HN: Tool to download scientific journal archives? on Tuesday October 06, 2020 @08:56AM (#24697167)
Okay, where can I find a summary of the relevant legislation, or is something to this effect written in the T&C?

Ask HN: Tool to download scientific journal archives?

Given organisational or personal access to a scientific journal (e.g. IEEE publications, Physical Review Letters, Proceedings of Symposia in Applied Mathematics, etc.), I assume it is legal to download all available papers that we have access to, for our own personal reference.Are there tools available to download the archives of any scientific journals? i.e. a tool which could download every...

( Read More... | 2 comments | on HN )
Re:Ask HN: Is Education Envied? on Sunday April 26, 2020 @03:06AM (#22985186)
> if there's something I really want then I will do what it takes to get it.

Ominous...

Re:Ask HN: Do you want an App that teaches you Physics? on Sunday April 26, 2020 @02:43AM (#22985083)
I feel that you do not understand the magnitude of difficulty behind what you are attempting. You seem to think it's going to be a breeze; that you can solve all the problems that the MOOCs around haven't been able to solve. And you think you can do this because... well for no particular reason as far as I can tell. You haven't proposed any idea that is distinct from what is already out there and is evidently not working. E.g. Udacity.

> adding content based on the most common questions, and providing a low-friction way for students to ask questions about the content

My criticism was about individuals asking questions. "the most common questions" are not the best ones, and don't help those students aspiring to learn to a higher level, who tend to ask better and more personalised questions. In fact the better part of science is asking the right questions! It is a talent to do so. What you will receive is a sampling of the lowest common denominator. And most of those questions deserve a more tactful version of "RTFM". This is my experience from tutoring-- students mostly ask questions that were answered in the lectures, because they've been procrastinating and not watching them. Especially a problem when the students don't commit themselves to attending class in person. In fact the best low-friction way for students to ask questions is... to be present during the lecture and put their hand up.

> Frankly, outperforming random profs at random schools is a pretty low bar. I've already done this just by tutoring.

What you are proposing is nothing like 1-on-1 tutoring. Feedback is part of this process. Try asking a "medium" to tell you about your relative as you hold shut lips and a poker face. Similar to a professor trying to give a lecture to a room full of mice.

> It's rare that a live professor adds much value for me vs. some of the best professors online.

In that case you aren't asking the right questions, or you aren't going to a very good university. While my experience of in-person classes was sometimes astoundingly poor, I would never exchange them for an online lecture series. You can talk with a professor and learn from their expert way of thinking-- not just the content itself but the way they think about problems. You learn through interactive dialogue-- people in the real world call this "conversation". In addition, the collegiate atmosphere of study among the pupils is in my opinion an extremely important component in students keeping up with the content. Only the most disciplined people can sit down and complete all exercises from a MOOC without interaction with others.

> the real value-add I've had from professors is when they've done the content-development work to put together organized course materials and/or well-thought-out problem sets well-curated suggested readings.

I agree, being organised does help. This applies to many things in life. Many professors at universities are not organised because of the pressures put upon them by the university administration, and other such factors. Also the pressure to push through any mediocre students to pump the university's finances and public image.

You must understand that, while it isn't impossible that you could create such a platform that is as successful as you want it to be, the a priori knowledge around previous similar ventures tells us something about how that might turn out. If you believe your idea is different, then how? You have not identified any key differences between your approach and those that have failed...

I must admit I really only had a cursory glance. I didn't want to read the article as I already know how to use the basic commands. It's entirely possible I'm just a dummy and didn't see an obvious link. I wouldn't take my feedback too seriously, unless you receive the same feedback from others too.

I meant more that it would be nice if the website design itself clearly indicated the presence of other related posts. This is about post metadata which shouldn't be communicated solely in the post itself but also in the way that post is presented.

Hi, I had a quick look at the post and it didn't seem that it was part of a canonical series of posts. That may room for improvement on the website design.
Article titled _How to Manipulate Files and Strings from the Terminal_ does not mention terminal-based text editors. Brushing that aside, it also does not feature `cp`, `rm`, `find` or `git`...
Answer is right there at the top of the comments.

Commenter: "Anyone else having a hard time finding peer-reviewed scholarly articles saying that this is a safe and effective method?"

Video creator replied: "It’s simply a piece of exercise equipment and does not warrant medical studies like some type of a pharmaceutical drug"

The answer is no. In all likelihood it does not work. Also the video thumbnail clearly uses different camera setups for the before/after, and the difference could be due entirely to perspective. Not to mention photoshop editing etc.

As well as there being no scientific evidence, I also doubt if there's any proposed mechanism by which this would work. Without mechanism or evidence, it's 99% chance quackery.

Re:Ask HN: Do you want an App that teaches you Physics? on Saturday April 25, 2020 @10:56PM (#22983953)
You have described a system of learning consisting only of pre-manufactured content. I feel like the success of this venture is based on an improbable premise: that an education in physics is possible by listening without the opportunity to ask.

You have deigned to ask this very question on the forum. Presumably because finding a good answer by searching for existing content was not likely to address your question.

Now don't you think graduate-level physics is a little bit more hard and complicated to learn?

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